Ten-year update: NRG Oncology/National Surgical Adjuvant Breast and Bowel Project B-42 randomized trial: extended letrozole therapy in early-stage breast cancer

BACKGROUND

The National Surgical Adjuvant Breast and Bowel Project B-42 trial evaluated extended letrozole therapy (ELT) in postmenopausal breast cancer patients who were disease free after 5 years of aromatase inhibitor (AI)-based therapy. Seven-year results demonstrated a nonstatistically significant trend in disease-free survival (DFS) in favor of ELT. We present 10-year outcome results.

METHODS

In this double-blind, phase III trial, patients with stage I-IIIA hormone receptor-positive breast cancer, disease free after 5 years of an AI or tamoxifen followed by an AI, were randomly assigned to 5 years of letrozole or placebo. Primary endpoint was DFS, defined as time from random assignment to breast cancer recurrence, second primary malignancy, or death. All statistical tests are 2-sided.

RESULTS

Between September 2006 and January 2010, 3966 patients were randomly assigned (letrozole: 1983; placebo: 1983). Median follow-up time for 3923 patients included in efficacy analyses was 10.3 years. There was statistically significant improvement in DFS in favor of letrozole compared with placebo (hazard ratio [HR] = 0.85, 95% confidence interval [CI] = 0.74 to 0.96; P  = .01; 10-year DFS: placebo = 72.6%, letrozole = 75.9%, absolute difference = 3.3%). There was no difference in the effect of letrozole on overall survival (HR = 0.97, 95% CI = 0.82 to 1.15; P  = .74). Letrozole statistically significantly reduced breast cancer-free interval events (HR = 0.75, 95% CI = 0.62 to 0.91; P = .003; absolute difference in cumulative incidence = 2.7%) and distant recurrences (HR = 0.72, 95% CI = 0.55 to 0.92; P = .01; absolute difference = 1.8%). The rates of osteoporotic fractures and arterial thrombotic events did not differ between treatment groups.

CONCLUSIONS

The beneficial effect of ELT on DFS persisted at 10 years. Letrozole also improved breast cancer-free interval and distant recurrences without improving overall survival. Careful assessment of potential risks and benefits is necessary for selecting appropriate candidates for ELT.

Effects of CYP3A4 and CYP2C9 genotype on systemic anastrozole and fulvestrant concentrations in SWOG S0226

Objective & methods: This study tested associations of genotype-predicted activity of CYP3A4, other pharmacogenes, SLC28A7 (rs11648166) and ALPPL2 (rs28845026) with systemic concentrations of the endocrine therapies anastrozole and fulvestrant in SWOG S0226 trial participants. Results: Participants in the anastrozole-only arm with low CYP3A4 activity (i.e. CYP3A4*22 carriers) had higher systemic anastrozole concentrations than patients with high CYP3A4 activity (β-coefficient = 10.03; 95% CI: 1.42, 18.6; p = 0.025). In an exploratory analysis, participants with low CYP2C9 activity had lower anastrozole concentrations and higher fulvestrant concentrations than participants with high CYP2C9 activity. Conclusion: Inherited genetic variation in CYP3A4 and CYP2C9 may affect concentrations of endocrine therapy and may be useful to personalize dosing and improve treatment outcomes.

Clinical Utility of Genomic Recurrence Risk Stratification in Early, Hormone-Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer: Real-World Experience

BACKGROUND

RNA-based genomic risk assessment estimates chemotherapy benefit in patients with hormone-receptor positive (HR+)/Human Epidermal Growth Factor 2-negative (ERBB2-) breast cancer (BC). It is virtually used in all patients with early HR+/ERBB2- BC regardless of clinical recurrence risk.

PATIENTS AND METHODS

We conducted a retrospective chart review of adult patients with early-stage (T1-3; N0; M0) HR+/ERBB2- BC who underwent genomic testing using the Oncotype DX (Exact Sciences) 21-genes assay. Clinicopathologic features were collected to assess the clinical recurrence risk, in terms of clinical risk score (CRS) and using a composite risk score of distant recurrence Regan Risk Score (RRS). CRS and RRS were compared to the genomic risk of recurrence (GRS).

RESULTS

Between January 2015 and December 2020, 517 patients with early-stage disease underwent genomic testing, and clinical data was available for 501 of them. There was statistically significant concordance between the 3 prognostication methods (P < 0.01). Within patients with low CRS (n = 349), 9.17% had a high GRS, compared to 8.93% in patients with low RRS (n = 280). In patients with grade 1 histology (n = 130), 3.85% had a high GRS and 68.46% had tumors > 1 cm, of whom only 4.49% had a high GRS. Tumor size > 1cm did not associate with a high GRS.

CONCLUSION

Genomic testing for patients with grade 1 tumors may be safely omitted, irrespective of size. Our finds call for a better understanding of the need for routine genomic testing in patients with low grade/low clinical risk of recurrence.

Patient-reported tolerability of adjuvant ipilimumab (3 or 10 mg/kg) versus high-dose interferon alfa-2b for resected high-risk stage III-IV melanoma in phase III trial E1609

PURPOSE

Trial E1609 demonstrated superior overall survival with ipilimumab 3 mg/kg (ipi3) compared to high-dose interferon (HDI) for patients with resected high-risk melanoma. To inform treatment tolerability, we compared health-related quality of life (HRQoL), gastrointestinal (GI), and treatment-specific physical and cognitive/emotional symptoms. We also compared treatment-specific concerns between all arms.

METHODS

We assessed HRQoL using the Functional Assessment of Cancer Therapy-General, physical and cognitive/emotional concerns using the FACT-Biologic Response Modifier subscale, and GI symptoms with the Functional Assessment of Chronic Illness Therapy-Diarrhea subscale pre-treatment and every 3 months. The primary outcome was the difference in HRQoL at 3 months between ipi3/ipi10 vs. HDI.

RESULTS

549 patients (n = 158 ipi3; n = 191 ipi10; n = 200 HDI) were analyzed. 3-month completion was 58.7%. Compared to HDI, ipilimumab patients reported better HRQoL (ipi3 = 87.5 ± 14.6 vs. HDI = 74.7 ± 15.4, p < .001; ipi10 = 84.9 ± 16.5 vs. HDI, p < .001) and fewer physical (ipi3 = 22.3 ± 4.6 vs. HDI = 17.1 ± 5.4, p < .001; ipi10 = 21.8 ± 5.0 vs. HDI p < .001) and cognitive/emotional (ipi3 = 18.6 ± 4.4 vs. HDI = 15.0 ± 5.3, p < .001; ipi10 = 17.7 ± 4.8 vs. HDI p < .001) concerns, but worse GI symptoms (ipi3 = 40.8 ± 5.0 vs. HDI = 42.2 ± 2.9, p = .011; ipi10 = 39.5 ± 7.0 vs. HDI, p < .001). Fewer ipilimumab patients reported worsening treatment-specific concerns (e.g., 52% of ipi3 and 58% of ipi10 reported worsening fatigue vs. 82% HDI, p's < .001).

CONCLUSION

PROs demonstrated less toxicity of ipi3 compared to HDI and ipi10. Priorities for symptom management among patients receiving ipilimumab include GI toxicities, fatigue, weakness, appetite loss, arthralgia, and depression.

TRIAL REGISTRATION

NCT01274338, January 11, 2011 (first posted date) https://clinicaltrials.gov/ct2/show/NCT01274338?term=NCT01274338&draw=2&rank=1 .

N064A (Alliance): Phase II Study of Panitumumab, Chemotherapy, and External Beam Radiation in Patients with Locally Advanced Pancreatic Adenocarcinoma

BACKGROUND

This North Central Cancer Treatment Group (NCCTG) N064A (Alliance) phase II trial evaluated upfront chemoradiotherapy incorporating the EGFR inhibitor panitumumab, followed by gemcitabine and panitumumab for unresectable, non-metastatic pancreatic cancer.

METHODS

The treatment consisted of fluoropyrimidine and panitumumab given concurrently with radiotherapy followed by gemcitabine and panitumumab for 3 cycles followed by maintenance panitumumab. The primary endpoint was the 12-month overall survival (OS) rate and secondary endpoints included confirmed response rate (RR), OS, progression-free survival (PFS), and adverse events. Enrollment of 50 patients was planned and the study fully accrued.

RESULTS

Fifty-two patients were enrolled, but only 51 were treated and included in the analysis. The median age of patients was 65 years and 54.9% were women. Twenty-two patients received at least 1 cycle of systemic therapy following radiotherapy, but 29 patients received chemoradiotherapy only without receiving subsequent chemotherapy after completion of chemoradiotherapy. The overall RR was 5.9% (95% CI: 1.2%-16.2%). The 12-month OS rate was 50% (95% CI: 38%-67%) which fell short of the per-protocol goal for success (51.1%). The median PFS was 7.4 months (95% CI: 4.5-8.6) and the median OS was 12.1 months (95% CI 7.9-15.9). Grade 3 or higher adverse events were reported by 88%.

CONCLUSION

The combination of panitumumab, chemotherapy, and external beam radiation therapy was associated with very high rates of grades 3-4 toxicities and survival results did not meet the trial's goal for success. This regimen is not recommended for further study (ClinicalTrials.gov Identifier NCT00601627).

Primary analysis from the phase 2 study of continuous talazoparib (TALA) plus intermittent low-dose temozolomide (TMZ) in patients with relapsed or refractory extensive-stage small cell lung cancer (ES-SCLC)

8517

Background: TALA exhibits cytotoxic effects by inhibiting poly (ADP-ribose) polymerase (PARP) proteins 1 and 2 in addition to “trapping” PARP on DNA. TMZ has been shown to increase antitumor response when combined with TALA in SCLC models (Wainberg AACR 2016). TALA plus TMZ as second-line therapy for ES-SCLC may improve disease-related outcomes. Methods: This is a phase 2, open-label, single-arm study of the safety and efficacy of TALA plus TMZ in patients with ES-SCLC, relapsed or refractory to a first-line platinum-based regimen. Participants receive TALA 0.75 mg (or 0.5 mg if creatinine clearance < 60 mL/min) po daily on 28-day cycles with TMZ 37.5 mg/m2 po on days 1-5. The primary endpoint is objective response rate (ORR) based on RECIST 1.1 criteria, versus a historical control of 15% ORR in second-line topotecan, with the null hypothesis rejected for 8 or more confirmed responses among 28 evaluable subjects (29% ORR). Secondary endpoints include progression-free survival, overall survival, duration of response, and time to response. Exploratory endpoints include biomarker studies such as status of DNA damage response genes (DDR) and patient reported outcomes. A Simon two-stage design was utilized to reach a total accrual of 28 evaluable patients. Results: Thirty-one subjects were enrolled, of which 3 were non-evaluable due to ineligibility (1) or early withdrawal of consent prior to first disease assessment (2). Eleven of 28 evaluable subjects (39.3%) achieved a confirmed partial response. The ORR was similar among platinum-refractory (3/6), -resistant (4/9), and -sensitive subgroups (4/13). The median time to response was 1.8 months (m), duration of response 5.8 m, progression free survival 4.5 m, and overall survival 11.9 m. Adverse events (AEs) were manageable, with grade ≥ 3 AEs being thrombocytopenia (61.3%), anemia (54.8%), neutropenia (41.9%), and atypical pneumonia (3.2%), which responded well to dose-hold or dose-reduction and transfusion or growth factor support as needed. Cell free DNA and tissue analysis demonstrated no germline DDR mutations among the trial subjects, but somatic DDR mutations at baseline and acquired during treatment were common. Three subjects remain on study treatment. Conclusions: The study exceeded its target response rate. This is the second trial to demonstrate a benefit of PARP inhibition with low-dose TMZ in SCLC (see Farago Cancer Discovery 2019). A phase 3 study is appropriate to confirm the benefit of this approach compared to currently approved options. Clinical trial information: NCT03672773.

Clinical utility of genomic recurrence risk stratification in early, hormone receptor–positive, human epidermal growth factor receptor 2–negative breast cancer

546

Background: RNA-based genomic assessment of recurrence risk is used to estimate chemotherapy benefit in patients with hormone-receptor positive (HR+)/Human Epidermal Growth Factor 2-negative ( ERBB2-) breast cancer (BC). While originally validated in patients who met established clinicopathologic guidelines for consideration of adjuvant chemotherapy, it is virtually used in all patients with early HR+/ ERBB2- BC regardless of clinical recurrence risk. Methods: We conducted a retrospective chart review of adult patients with early-stage (T1-3; N0; M0) HR+/ ERBB2- BC who underwent genomic risk assessment of recurrence using the Oncotype DX (Exact Sciences) 21-genes assay, between January 2015 and December 2020. Clinicopathologic features were collected to assess the clinical recurrence risk. A low clinical risk score (CRS) was defined as a tumor size ≤ 3 cm in diameter with histologic grade 1, or ≤ 2 cm with grade 2 or ≤ 1 cm with grade 3. A composite risk score of distant recurrent (RRS), derived from a COX model using data from the SOFT and TEXT trials ( https://rconnect.dfci.harvard.edu/CompositeRiskSTEPP/ ), was also computed for 374 patients for whom clinical data was available. RRS > 1.42 was defined as high. High genomic risk of recurrence was defined as a score (GRS) ≥25. The data was collected under IRB approval. Results: A total of 517 patients with early-stage disease were referred for genomic testing, and clinical data was available for 501 of them. Median age was 69 years (IQR=13), median tumor size 1.03 cm (IQR=0.9), and grade 2 histology (57.49%) was the most common. Results of recurrence risk, using the 3 prognostication methods, are summarized in Table. Within patients with low CRS (n=349), 9.17% had a high GRS, compared to 8.93% in patients with low RRS (n=280). In patients with grade 1 histology (n=130), 3.85% had a high GRS and 68.46% had tumors > 1cm, of whom only 4.49% had a high GRS. Tumor size > 1cm did not associate with a high GRS (Fisher’s Exact test; P=1.00). Conclusions: In patients with early HR+/ ERBB2- BC, <10% of patients with low clinical risk, and <5% of patients with grade 1 tumors, had a high genomic recurrence risk, respectively. Given current NCCN recommendation for testing, our findings raise the question of whether genomic testing for patients with grade 1 tumors can be safely omitted, irrespective of size, and call for a better understanding of the need for routine genomic testing in patients with low grade/low clinical risk of recurrence. [Table: see text]

TRIO-US B-12 TALENT: Phase II neoadjuvant trial evaluating trastuzumab deruxtecan with or without anastrozole for HER2-low, HR+ early-stage breast cancer

TPS623

Background: Although patients with hormone receptor-positive (HR+)/HER2-negative breast cancer (BC) frequently experience disease response to neoadjuvant therapy, fewer than 10% achieve a pathologic complete response (pCR) with standard chemotherapy or endocrine therapy, even in combination with CDK4/6 inhibitors. Thus, finding more effective therapies for this disease remains an area of unmet need. HER2 amplification is a known driver of endocrine resistance and HER2 may be expressed at a low level (IHC 1+ or 2+) in approximately 60% of HR+ BC. Trastuzumab deruxtecan (DS-8201a, T-DXd) is a novel HER2-targeting antibody drug conjugate (ADC) that is FDA approved in the US for HER2-positive (with boxed warnings for interstitial lung disease) and has demonstrated promising clinical efficacy in HER2-low BC with an objective response rate of ̃37%. The aim of TALENT (TRIO-US B-12, NCT04553770) is to evaluate the clinical activity and safety of neoadjuvant T-DXd alone or in combination with endocrine therapy in patients with HR+/HER2-low early BC. Methods: This is an ongoing randomized, multicenter, open-label, two-stage, phase II neoadjuvant trial for participants with early stage, HR+, HER2-low (1+ or 2+/ISH- by IHC) BC. Eligible participants include men and women with previously untreated, operable invasive BC greater than 2.0 cm (cT2). Pts with recurrent, metastatic, or inflammatory BC are excluded. Pts are randomized 1:1 to receive six to eight cycles of T-DXd (5.4 mg/kg IV q21 days) alone or in combination with anastrozole AI (1 mg PO QD). Men and pre/peri menopausal women randomized to the AI arm also receive routine care GnRH agonist. Stratification factors include HER2 expression and menopausal status (men stratified as postmenopausal). Tumor tissue is taken at baseline, cycle 1 day 17-21, and at surgery. Blood samples are taken at 4 time points for biomarker analysis. The primary endpoint is pCR rate (breast and lymph node) at definitive surgery. In stage I, 58 participants will be randomized (29/arm). If >2 participants in an arm achieve pCR, that arm will expand (stage II) to enroll an additional 15 participants (total of 44/arm). A pCR rate of > 10% (5/44) would be considered favorable, warranting further evaluation in a larger trial. Other endpoints include safety, changes in Ki67 expression, Residual Cancer Burden index, biomarker analysis (including serial cfDNA analysis), and health-related quality of life. As of January 2022, 37 participants have enrolled, 24 have completed treatment, and 14 have had surgery. To our knowledge this is the first and only ongoing study evaluating T-DXd with or without endocrine therapy for HR+, HER2-low BC in the neoadjuvant setting. The study will shed light on clinical activity and biomarkers, which may guide larger confirmatory studies for this population. Clinical trial information: NCT04553770.

Cetuximab and Irinotecan With or Without Bevacizumab in Refractory Metastatic Colorectal Cancer: BOND-3, an ACCRU Network Randomized Clinical Trial

Background

Combination irinotecan and cetuximab is approved for irinotecan-refractory metastatic colorectal cancer (mCRC). It is unknown if adding bevacizumab improves outcomes.

Patients and Methods

In this multicenter, randomized, double-blind, placebo-controlled phase II trial, patients with irinotecan-refractory RAS-wildtype mCRC and no prior anti-EGFR therapy were randomized to cetuximab 500 mg/m², bevacizumab 5 mg/kg, and irinotecan 180 mg/m² (or previously tolerated dose) (CBI) versus cetuximab, irinotecan, and placebo (CI) every 2 weeks until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), and adverse events (AEs).

Results

The study closed early after the accrual of 36 out of a planned 120 patients due to changes in funding. Nineteen patients were randomized to CBI and 17 to CI. Baseline characteristics were similar between arms. Median PFS was 9.7 versus 5.5 months for CBI and CI, respectively (1-sided log-rank P = .38; adjusted hazard ratio [HR] = 0.64; 95% confidence interval [CI], 0.25-1.66). Median OS was 19.7 versus 10.2 months for CBI and CI (1-sided log-rank P = .02; adjusted HR = 0.41; 95% CI, 0.15-1.09). ORR was 36.8% for CBI versus 11.8% for CI (P = .13). Grade 3 or higher AEs occurred in 47% of patients receiving CBI versus 35% for CI (P = .46).

Conclusion

In this prematurely discontinued trial, there was no significant difference in the primary endpoint of PFS between CBI and CI. There was a statistically significant improvement in OS in favor of CBI compared with CI. Further investigation of CBI for the treatment of irinotecan-refractory mCRC is warranted.

Clinical Trial Registration: NCT02292758

Abstract P2-14-02: Overall survival following treatment with a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer

Background: SV-BR-1-GM is a GM-CSF secreting breast cancer cell line derived from a Grade II (moderately differentiated) breast tumor that also expresses HLA class I & II antigens and is able to function as an antigen-presenting cell. Irradiated SV-BR-1-GM is used in a regimen including pre-dose low-dose cyclophosphamide and post-dose injection of IFNα2b into the inoculation sites. The SV-BR-1-GM regimen has been used alone (“monotherapy”, ClinicalTrials.gov NCT03066947 - study completed) and in combination with checkpoint inhibitors (“combination”, ClinicalTrials.gov NCT03328026 - study ongoing). Here we report survival data for patients with advanced metastatic breast cancer (aMBC) treated with the SV-BR-1-GM regimen. Methods: 27 patients with refractory aMBC were treated with the SV-BR-1-GM regimen as monotherapy (cycles every 2 weeks x3 and then monthly). The combination study uses the SV-BR-1-GM regimen with PD-1 inhibitors (PD-1i) pembrolizumab or retifanlimab with cycles every 3 weeks (12 patients dosed to date). Here we report progression free survival (PFS) and overall survival (OS) for patients where that data was collected. Results: A total of 35 patients received the SV-BR-1-GM regimen. The SV-BR-1-GM regimen alone (monotherapy) was given to 27 and 12 received the regimen with a PD-1i checkpoint inhibitor (combination therapy): 4 subjects crossed over from monotherapy. Patients had been heavily pre-treated, median prior regimens = 5. Most patients were estrogen receptor and/or progesterone receptor positive, 18% were Her2/neu positive and 33% were triple negative. The treatment was generally safe and well tolerated. The disease control rate was 30% for the SV-BR-1-GM regimen alone and 33% for the combination with a PD-1i. Several patients had objective complete regression of selected metastases. Median progression free survival was 2.8 months for the SV-BR-1-GM regimen alone and 4.2 months for the PD-1i combination. Median overall survival was 7.0 months for the SV-BR-1-GM regimen alone (data available on 9 patients), and 12.0 months for the PD-1i combination (data available on 7 patients). Conclusions: The median OS compares favorably with published data regarding survival in third line trials (Kazmi Breast Cancer Res Treat. 2020 Aug 17). The protracted OS seen in some subjects suggests some patient subpopulations are more likely to derive clinical benefit. The SV-BR-1-GM regimen alone or in combination with a PD-1i, when administered to heavily pre-treated patients with aMBC, may have elicited effective immune responses in some patients.

TablePatients by StudyCharacteristicSV-BR-1-GM Regimen Alone (n=27)SV-BR-1-GM Regimen + PD-1i (n=12)All Patients* (n=35)Age60 ± 1063 ± 1060 ± 10Mean Prior Systemic Regimens5 (range 0-12)6 (range 1-10)5 (range 0-12)% ER/PR +52%75%58%% Her2/neu +15%17%18%% Triple Negative36%25%33%Delayed-type Hypersensitivity81%91%82%Disease Control Rate30%33%29%Median (Range) Progression Free Survival (months)2.8 (0.4-7.4) (n=27)4.2 (0.8-9.4) (n=11)2.8 (0.4-9.4) (n=34)Median (Range) Overall Survival (months)7.0 (1-41) (n=9)12.0 (5.1-21.4) (n=7)10.2 (1-41) (n=14)• Note that 4 patients crossed over from the monotherapy study to the combination therapy study.

Citation Format: William Williams, Shaker R Dakhil, Carmen Calfa, Jarrod P Holmes, Saveri Bhattacharya, Jason Lukas, Elizabeth Tan-Chui, George E Peoples, Vivek G Sunkari, Markus D Lacher, Charles L Wiseman. Overall survival following treatment with a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-14-02.

Abstract PD15-05: Assessment of estrogen receptor (ESR1) mRNA expression for prediction of extended aromatase inhibitor benefit in HR-positive breast cancer using NRG Oncology/NSABP B-42

Background: In NSABP B-14, the quantitative levels of ESR1 mRNA, assessed using the standardized 21-gene assay and qRT-PCR platform predicted tamoxifen benefit (interaction p-value &lt;0.001). NSABP B-42 evaluated the effect of extended letrozole in postmenopausal women with hormone receptor-positive breast cancer who have completed 5 years of hormonal therapy with either an aromatase inhibitor or tamoxifen followed by an aromatase inhibitor. We proposed to determine if ESR1 mRNA, reported as the quantitative ER single gene score, is predictive of the magnitude of benefit from extended adjuvant endocrine therapy with letrozole in patients enrolled in NSABP B-42. Methods: This prospectively planned retrospective study used a stratified cohort sample drawn from the 2,589 B-42 patients with available tumor tissue blocks and appropriate consent. All 133 patients who experienced distant recurrence and 48 patients who experienced local/regional but not distant recurrence were included along with a stratified random sample of 547/2,408 patients without recurrence. The primary endpoint was distant recurrence. The primary analysis tested for the interaction between the continuous ER single gene score and the effect of extended letrozole treatment using a weighted Cox proportional hazards regression model. A secondary analysis considered the ER single gene score categorized using the prespecified cutoff of ≤9.1 versus &gt;9.1. Recurrence-free interval was a secondary endpoint. Results: The results of the assay were available for 587 patients. The median ER score was 10.2 (IQR 9.3-11.0). There were 131 patients (23.2% weighted) with ER ≤9.1 and 456 (76.8% weighted) with ER &gt;9.1. No significant interaction of the effect of extended letrozole treatment was found for either the ER single gene score (interaction hazard ratio letrozole vs. placebo with an IQR change in ER score 1.10, 95% CI 0.66 - 1.82, p=.72) or the categories ER ≤9.1 (treatment HR=0.40, 95% CI 0.15-1.06) or ER &gt;9.1 (treatment HR=0.70, 95% CI 0.43-1.12) (interaction p=.32). There was also no apparent prognostic effect of the ER single gene score for distant recurrence with placebo treatment after 5 years of endocrine therapy (p=.12). Results were similar in analyses of any recurrence, analyses adjusting for the proliferation axis from the 21-gene assay, and subgroup analyses by nodal and HER2-status. Conclusions: The B-42 study provided no evidence that ESR1 mRNA as measured by the ER single gene score can inform decisions regarding extended letrozole therapy after 5 years of adjuvant endocrine therapy. Confidence intervals were relatively wide but rule out a strong predictive effect of the ER single gene score in the expected direction. Support: U10CA180868, -180822, U24CA196067; Novartis; Exact Sciences

Citation Format: Eleftherios Mamounas, Hanna Bandos, Priya Rastogi, Michael R Crager, Carolyn Mies, Peter C Lucas, Charles E Geyer, Jr, Louis Fehrenbacher, Mark L Graham, Stephen KL Chia, Adam M Brufsky, Janice M Walshe, Gamini S Soori, Shaker R Dakhil, Soonmyung Paik, Sandra M Swain, Frederick L Baehner, Steven Shak, Norman Wolmark. Assessment of estrogen receptor (ESR1) mRNA expression for prediction of extended aromatase inhibitor benefit in HR-positive breast cancer using NRG Oncology/NSABP B-42 [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD15-05.

A randomized phase II trial of MEK and CDK4/6 inhibitors vesus tipiracil/trifluridine (TAS-102) in metastatic KRAS/NRAS mutant (mut) colorectal cancer (CRC)

116

Background: Constitutively activating KRAS or NRAS muts occur in ̃50% of CRC, increasing RAF-MEK-ERK signaling and causing overexpression of cyclin D1, which binds to cyclin dependent kinase 4/6 (CDK4/6) to drive cell cycle progression. Combination MEK and CDK4/6 inhibitors caused tumor regression in patient-derived xenografts of KRAS mut CRC. We hypothesized that binimetinib and palbociclib (B+P) would improve progression-free survival (PFS) compared to TAS-102 in refractory KRAS/NRAS mut mCRC. Methods: ACCRU-GI-1618 was a multicenter, randomized phase II clinical trial (NCT03981614). Key inclusion criteria were KRAS/NRAS mut mCRC, with prior fluoropyrimidine/ oxaliplatin/ irinotecan/ anti-VEGF therapy. There was a 6-patient safety run-in with binimetinib 30 mg po BID D1-28 and palbociclib 100 mg po daily D1-21. After, patients were randomized 1:1 to B+P vs TAS-102 (stratified by KRAS mut type and prior regorafenib use), with optional crossover at progression. The primary endpoint was PFS; 73 PFS events (from a sample size of 112) provided 90% power to detect improvement of PFS (hazard ratio = 0.5, i.e. median PFS of 2 vs. 4 months) with 1-sided α = 0.05. A prespecified interim analysis for futility was planned after 37 PFS events were observed, with completion of accrual if 1-sided stratified log-rank p-value < 0.551. Hazard ratios (HR) and 95% confidence intervals (CI) are estimated by stratified Cox proportional hazards models. Results: After the safety run-in, 93 patients at 6 sites were randomized; 82 (41 B+P, 41 TAS-102) comprise the primary analysis population (eligible, consented, and started treatment). In this population, median age was 52 years, 50% female, 68% left-sided, 79% with KRAS codon 12/13 mut, 12% with prior regorafenib. Enrollment was halted at interim analysis as the futility boundary was crossed (1-sided p = 0.67). At final analysis, 68 subjects had a PFS event (34 in each arm). Median PFS was 2.1 mo (95% CI 2.0-3.0) with B+P vs 2.1 mo (2.0-2.4) with TAS-102; HR 0.86 (0.52-1.44). 4-mo PFS rate was 22.2% (11.9-41.6) with B+P vs 10.6% (3.8-30.0) with TAS-102. With 37 OS events (14 in B+P arm), median OS was 7.7 mo (5.1-NE) with B+P vs 6.6 mo (4.8-8.9) with TAS-102; HR 0.77 (95% CI 0.39-1.51). TAS-102 had greater grade 3-4 hematologic AEs (46% vs 22%), and B+P had more grade 3-4 non-hematologic AEs (47% vs 32%). Grade 3-4 AEs more common with B+P were fatigue (8% vs 0%), oral mucositis (6% vs 0%), and nausea (4% vs 2%). Though 63% of patients on B+P had acneiform rash, only 2% was grade 3-4. Grade 1-2 diarrhea occurred in 35% of B+P and 24% of TAS-102 patients. No new safety signal was observed. Conclusions: B+P did not significantly improve median PFS or OS compared to TAS-102 in KRAS/NRAS mut mCRC. Subgroup analyses and translational studies are ongoing to determine which subgroups may be more likely to attain 4-mo PFS or identify mechanisms of resistance. Clinical trial information: NCT03981614.

OUP accepted manuscript

Background

Liquid biopsy testing offers a significant potential in selecting signal-matched therapies for advanced solid malignancies. The feasibility of liquid biopsy testing in a community-based oncology practice, and its actual impact on selecting signal-matched therapies, and subsequent survival effects have not previously been reported.

Patients and Methods

A retrospective chart review was conducted on adult patients with advanced solid cancer tested with a liquid-biopsy assay between December 2018 and 2019, in a community oncology practice. The impact of testing on treatment assignment and survival was assessed at 1-year follow-up.

Results

A total of 178 patients underwent testing. A positive test was reported in 140/178 patients (78.7%), of whom 75% had an actionable mutation. The actual overall signal-based matching rate was 17.8%. While 85.7% of patients with no actionable mutation had a signal-based clinical trial opportunity, only 10% were referred to a trial. Survival analysis of lung, breast, and colorectal cancer patients with actionable mutations who received any therapy (n = 66) revealed a survival advantage for target-matched (n = 22) compared to unmatched therapy (n = 44): patients who received matched therapy had significantly longer progression-free survival (PFS) (mPFS: 12 months; 95%CI, 10.6-13.4 vs. 5.0 months; 95%CI, 3.4-6.6; P = .029), with a tendency towards longer overall survival (OS) (mOS: 15 months; 95%CI, 13.5-16.5 vs. 13 months; 95%CI: 11.3-14.7; P = .087).

Conclusions

Implementation of liquid biopsy testing is feasible in a US community practice and impacts therapeutic choices in patients with advanced malignancies. Receipt of liquid biopsy-generated signal-matched therapies conferred added survival benefits.

Circulating tumor DNA (ctDNA) mutations may predict treatment response in extensive-stage small cell lung cancer (ES-SCLC) treated with talazoparib and temozolomide (TMZ)

8564

Background: Poly (ADP-ribose) polymerase (PARP) inhibition in combination with TMZ is a promising treatment strategy for ES-SCLC. In SCLC models, talazoparib, a potent PARP inhibitor, exhibits cytotoxic effects by inhibiting PARP proteins 1/2 and trapping PARP on DNA while TMZ potentiates antitumor response by contributing to genomic instability (Wainberg 2016). Prior ctDNA studies in SCLC have suggested that treatment precipitates the appearance of DNA repair alterations (Nong 2018), but it is unknown whether homologous recombination deficiency (HRD) predicts for treatment response with this combination. Methods: Patients (pts) with relapsed or refractory ES-SCLC were treated with oral talazoparib 0.75 mg daily on 28-day cycles and oral TMZ 37.5 mg/m2 on days 1-5 in a phase 2 clinical trial (UCLA/TRIO-US L-07, NCT03672773). ctDNA was collected and assessed based on allele frequency and plasma copy number at baseline and every 8 weeks during treatment with the Guardant360 assay (Redwood City, CA). HRD was defined as a deletion or missense mutation known or likely to result in aberrant expression of ATM or BRCA1/2 (other HRD genes not detected by assay). Response to treatment was defined by RECIST 1.1 criteria. Fisher’s exact tests were used to compare proportions of patients with P-values < 0.05 considered statistically significant ( www.r-project.org , Vienna, AU). Results: For 15 evaluable pts in the first Simon stage of this trial, 45 ctDNA samples were collected. The most common baseline genetic alterations were mutations in TP53 (14 pts), BRCA2 (5 pts), ATM (4 pts), and RB1 (3 pts). Of those with > 1 ctDNA timepoint collected, 10/11 (90.9%) pts had ≥1 new mutation (range 1-19) detected after receiving treatment (range 8-35 weeks), most commonly in ATM (5 pts). Overall, 5 pts had confirmed partial responses (PR), 7 had stable disease, and 3 had progressive disease. Disease control (DC) was associated with the presence of new mutations (P = 0.022) and was more common in those with HRD, with DC in 9/10 (90.0%) HRD pts vs 3/5 (60.0%) pts without HRD. All those with PRs experienced a ctDNA nadir at 8 weeks of treatment with nearly all (4/5, 80.0%) exhibiting HRD, 2 at baseline and 2 at 8 weeks of treatment. Conclusions: Mutations in DNA repair genes occur on treatment with talazoparib and TMZ and may associate with disease control. With a response rate of 33% in the first Simon stage of this trial, the TRIO-US L-07 trial exploring the combination of talazoparib and TMZ will be assessed in 13 additional patients, after which additional ctDNA analyses will be performed on the cohort as a whole. Clinical trial information: NCT03672773.

Breast Cancer Index (BCI) and prediction of benefit from extended aromatase inhibitor (AI) therapy (tx) in HR+ breast cancer: NRG oncology/NSABP B-42

501

Background: The BCI HOXB13/IL17BR ratio (BCI-H/I) has been shown to predict endocrine tx (ET) and extended ET (EET) benefit. We examined the effect of BCI-H/I for EET benefit prediction in NSABP B-42, evaluating extended letrozole tx (ELT) in HR+ breast cancer patients (pts) who completed 5 yrs of ET. Methods: All pts with available primary tumor tissue were eligible. Primary endpoint was recurrence-free interval (RFI). Secondary endpoints were distant recurrence (DR), breast cancer-free interval (BCFI), and disease-free survival (DFS). Stratified Cox proportional hazards model was used. Due to a non-proportional effect of ELT on DR, time-dependent secondary analyses (≤4y, >4y) were performed. Likelihood ratio test evaluated treatment by BCI-H/I interaction. Results: In 2,179 pts analyzed (60% N0; 62% AI only; 80% HER2-), 45% were BCI-H/I-High and 55% BCI-H/I-Low. ELT showed an absolute 10y benefit of 1.6% for RFI (HR=0.77, 95% CI 0.57-1.05, p=0.10) (BCI-H/I-Low: 1.1% [HR=0.69, 0.43-1.11, p=0.13]; BCI-H/I-High: 2.4% [HR=0.83, 0.55-1.26, p=0.38]; interaction p=0.55). There was no statistically significant ELT by BCI-H/I interaction for BCFI (BCI-H/I-Low: HR=0.53, 0.36-0.78, p=0.001; BCI-H/I-High: HR=0.85, 0.60-1.21, p=0.36; interaction p=0.07) or for DFS (BCI-H/I-Low: HR=0.75, 0.58-0.95, p=0.017; BCI-H/I-High: HR=0.81, 0.64-1.04, p=0.09; interaction p=0.62). Before 4y, there was no statistically significant ELT benefit on DR in either BCI-H/I group. After 4y, BCI-H/I-High pts had statistically significant ELT benefit on DR (HR: 0.29, 0.12-0.69, p=0.003), while BCI-H/I-Low pts were less likely to benefit (HR: 0.68, 0.33-1.39, p=0.28) (interaction p=0.14). Conclusions: BCI-H/I prediction of ELT benefit on RFI was not confirmed. In time-dependent DR analyses, BCI-H/I-High pts had statistically significant benefit from ELT after 4y, while BCI-H/I-Low pts did not. Observed ELT benefit on BCFI in BCI-H/I-Low pts was primarily driven by second primary breast cancers. Additional follow-up is needed to further characterize BCI-H/I predictive ability in this study. Support: U10CA180868, -180822, U24CA196067; Novartis; Biotheranostics. Clinical trial information: NCT00382070. [Table: see text]

Utility of the 70-gene MammaPrint assay for prediction of benefit from extended letrozole therapy (ELT) in the NRG Oncology/NSABP B-42 trial

502

Background: The 70-gene MammaPrint (MP) assay predicts risk of distant recurrence (DR) in hormone-receptor positive early-stage breast cancer and classifies cancers as Low Risk or High Risk. NSABP B-42 evaluated ELT in patients (pts) who had completed 5 yrs of adjuvant endocrine therapy (tx). The primary objective was to determine the utility of MP to identify pts enrolled in NSABP B-42 who are likely to benefit from ELT. Methods: A total of 1,866 pts from B-42 had available MP results. Primary endpoint is DR. Secondary endpoints are disease-free survival (DFS) and breast cancer-free interval (BCFI). For the primary analysis, pts were classified as High Risk (MP-H) (MP score ≤0.000) or Low Risk (MP-L) (MP score > 0.000). Exploratory analyses were performed for MP-L subcategories: MP Ultralow Risk (MP-UL) (MP score > 0.355) and MP-L but not MP-UL (MP-LNUL) (MP score > 0.000, ≤0.355). Likelihood ratio test based on stratified Cox proportional hazards (PH) model was used for treatment by risk group interaction. Stratified log-rank test was used to compare treatment groups. Hazard ratios and 95% CI were computed based on the stratified Cox PH model. Results: Among 1,866 pts, 706 (38%) were MP-H and 1,160 (62%) were MP-L. Of the MP-L, 252 (22%) were MP-UL. There were no significant differences in the distribution of patient and tumor characteristics between the MP group and the rest of the B-42 cohort, except for HER2 status. ELT effect was more pronounced in the MP cohort than in the overall B-42 population. For DR, there was statistically significant ELT benefit in MP-L (HR = 0.43, 95% CI 0.25-0.74, p = 0.002), but not MP-H (HR = 0.65, 0.34-1.24, p = 0.19) (interaction p = 0.38). For DFS, there was statistically significant ELT benefit in MP-L, but not MP-H (interaction p = 0.015). Similar findings were observed for BCFI (interaction p = 0.006). Within subcategories of MP-L, there was statistically significant ELT benefit in MP-LNUL, but not in MP-UL for all three endpoints, however the power in MP-UL was limited due to low number of pts (Table). Clinical trial information: 00382070. Conclusions: Statistically significant ELT benefit was observed for MP-L, but not MP-H. The treatment by risk group interaction was not statistically significant for DR, but it was for DFS and BCFI. The benefit appears to be stronger in MP-LNUL than in MP-UL. NCT: 00382070. Support: U10CA180868, -180822, U24CA196067; Novartis; Agendia.[Table: see text]

Liquid biopsy testing: Impact on treatment assignment and survival in a community-based oncology practice—A real-world experience

3027

Background: Liquid biopsy is a promising, rapid and minimally invasive genetic test examining circulating tumor DNA. It offers a significant potential in selecting signal-matched therapeutic options. Methods: A retrospective chart review was conducted on adult patients with advanced solid cancer whose tumors were tested with the Guardant 360® (Guardant Health) assay between December 2018 and 2019. A follow-up analysis (censor date: 01/06/2021) was carried to assess the actual impact of testing results on treatment assignment and survival. Results: A total of 178 patients underwent testing. Mean age at diagnosis was 65 years. Median (m) Karnofsky Performance Scale was 90% and the majority of patients (89.9%) had ≥ stage III-B disease. Lung (LCa; 50.56%), breast (BCa; 17.42%) and colorectal (CRCa; 7.87%) cancers were the most common cancer types. A positive test was reported in 140/178 patients (78.7%); of those, 105/140 (75%) had an actionable mutation, either with an FDA-approved target-matched therapy (n = 32/105; 30.5%) or with a therapy outside current FDA indication (n = 73/105; 69.5%). In patients with no actionable mutation (n = 35/140; 25%), 85.7% (n = 30/35) had a signal-based clinical trial opportunity. The actual overall signal-based matching rate was 17.8% (24/135; vs. 82.2% no-match rate). Within candidates for FDA-approved treatment, 50% (16/32) received targeted therapy while only 6.9% (5/73) were treated with targeted agents outside current FDA indication: mean matching score (number of matched drugs/number of actionable mutations) was 0.6 (range: 0.33-2) and 0.8 (range: 0.17-2), respectively. Only 10% (3/30) were referred to signal-based clinical trials. Survival analysis of LCa, BCa and CRCa patients with actionable mutations who actually received any therapy (n = 66) revealed post-testing survival advantage for target-matched therapy (n = 22) compared to unmatched therapy (n = 44): overall survival (OS) was longer in the matched cohort (mOS: 13.3 months; 95% CI: 11.8-14.8 vs. 10.7 months; 95% CI: 9-12.4 in unmatched) but did not reach statistical significance ( P = 0.09). Progression free survival (PFS) was significantly longer in patients who received matched therapy (mPFS: 11.3 months; 95% CI: 9.9-12.7 vs. mPFS: 6.8 months; 95% CI: 5.1-8.5 in unmatched; P < 0.05). Conclusions: Implementation of liquid biopsy testing is feasible in community practice and impacts therapeutic choices in patients with advanced malignancies. Receipt of liquid biopsy-generated signal-matched precision therapies conferred added survival benefit compared to unmatched therapy. Larger sample size studies are needed to validate these findings.

KRYSTAL-12: A randomized phase 3 study of adagrasib (MRTX849) versus docetaxel in patients (pts) with previously treated non-small-cell lung cancer (NSCLC) with KRASG12C mutation

TPS9129

Background: Despite significant advances in chemotherapy and immunotherapy for advanced NSCLC, the majority of pts ultimately develop progressive disease associated with poor outcomes. KRAS is a key mediator of the RAS/MAPK signaling cascade that promotes cell growth and proliferation. KRASG12C mutations occur in 14% of NSCLC (adenocarcinoma), and mutations in KRAS are associated with a poor prognosis. Although KRAS has historically been undruggable, recent research into the development of agents that specifically bind mutant KRAS has led to the development of direct inhibitors of KRASG12C. Adagrasib, an investigational agent, is a potent, covalent inhibitor of KRASG12C that irreversibly and selectively binds to and locks KRASG12C in its inactive state. Adagrasib was optimized for favorable pharmacokinetic (PK) properties, including oral bioavailability, long half-life (̃24 h), and extensive tissue distribution. Initial results have demonstrated encouraging antitumor activity and tolerability of adagrasib monotherapy in pts with NSCLC harboring a KRASG12C mutation. Methods: KRYSTAL-12 is a multicenter, randomized Phase 3 study evaluating the efficacy of adagrasib (600 mg BID) vs docetaxel in pts with advanced NSCLC harboring a KRASG12C mutation who have progressed during or after treatment with a platinum-based regimen and an immune checkpoint inhibitor. The study is designed to demonstrate improvement in the dual primary endpoints of progression-free survival (PFS) and overall survival (OS). Secondary endpoints include safety, objective response rate (ORR) per RECIST 1.1, duration of response (DOR), plasma PK parameters of adagrasib, and patient-reported outcomes (PROs). The study will also explore correlations between gene alterations (at baseline and upon development of treatment resistance) and efficacy. Approximately 450 patients will be randomized in a 2:1 ratio to receive adagrasib or docetaxel and will be stratified by region (United States/Canada vs other countries) and sequential vs concurrent administration of prior platinum-based chemotherapy and anti–PD-1/PD-L1 antibody. The planned sample size is sufficiently powered for the hypothesized treatment effect of the endpoints. Pts will receive study treatment until disease progression, unacceptable adverse events, investigator decision to terminate treatment, or patient withdrawal. This study is currently enrolling and will be open at sites in the United States, Europe, and Asia. Clinical trial information: NCT04685135.

Phase III Randomized Trial of Bisphosphonates as Adjuvant Therapy in Breast Cancer: S0307

BACKGROUND

Adjuvant bisphosphonates, when given in a low-estrogen environment, can decrease breast cancer recurrence and death. Treatment guidelines include recommendations for adjuvant bisphosphonates in postmenopausal patients. SWOG/Alliance/Canadian Cancer Trials Group/ECOG-ACRIN/NRG Oncology study S0307 compared the efficacy of three bisphosphonates in early-stage breast cancer.

METHODS

Patients with stage I-III breast cancer were randomly assigned to 3 years of intravenous zoledronic acid, oral clodronate, or oral ibandronate. The primary endpoint was disease-free survival (DFS) with overall survival as a secondary outcome. All statistical tests were two-sided.

RESULTS

A total of 6097 patients enrolled. Median age was 52.7 years. Prior to being randomly assigned, 73.2% patients indicated preference for oral vs intravenous formulation. DFS did not differ across arms in a log-rank test (P = .49); 5-year DFS was 88.3% (zoledronic acid: 95% confidence interval [CI] = 86.9% to 89.6%), 87.6% (clodronate: 95% CI = 86.1% to 88.9%), and 87.4% (ibandronate: 95% CI = 85.6% to 88.9%). Additionally, 5-year overall survival did not differ between arms (log rank P = .50) and was 92.6% (zoledronic acid: 95% CI = 91.4% to 93.6%), 92.4% (clodronate: 95% CI = 91.2% to 93.5%), and 92.9% (ibandronate: 95% CI = 91.5% to 94.1%). Bone as first site of recurrence did not differ between arms (P = .93). Analyses based on age and tumor subtypes showed no treatment differences. Grade 3/4 toxicity was 8.8% (zoledronic acid), 8.3% (clodronate), and 10.5% (ibandronate). Osteonecrosis of the jaw was highest for zoledronic acid (1.26%) compared with clodronate (0.36%) and ibandronate (0.77%).

CONCLUSIONS

We found no evidence of differences in efficacy by type of bisphosphonate, either in overall analysis or subgroups. Despite an increased rate of osteonecrosis of the jaw with zoledronic acid, overall toxicity grade differed little across arms. Given that patients expressed preference for oral formulation, efforts to make oral agents available in the United States should be considered.

Nivolumab and Ipilimumab as Maintenance Therapy in Extensive-Disease Small-Cell Lung Cancer: CheckMate 451

In extensive-disease small-cell lung cancer (ED-SCLC), response rates to first-line platinum-based chemotherapy are robust, but responses lack durability. CheckMate 451, a double-blind phase III trial, evaluated nivolumab plus ipilimumab and nivolumab monotherapy as maintenance therapy following first-line chemotherapy for ED-SCLC.

Abstract PS17-20: Response to a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer correlates with tumor grade

Background: SV-BR-1-GM is a GM-CSF transfected breast cancer cell line, exceptional for having antigen-presenting capability and expressing both HLA I and II. The parent cell line, SV-BR-1, was derived from a patient with grade II (moderately differentiated) breast cancer. We report molecular characterization of SV-BR-1-GM, noting it retains features of a grade II tumor, and report enhanced disease control in patients with grade I or II breast cancer.Methods: SV-BR-1 and SV-BR-1-GM were characterized molecularly using RNAseq and proteomic analyses. We treated 23 evaluable patients with recurrent and/or metastatic breast cancer refractory to standard therapy. The SV-BR-1-GM regimen included cyclophosphamide 300 mg/m2 2-3d prior to intradermal injection of SV-BR-1-GM (20-40x106 cells divided into 4 sites) and IFNα into the inoculation sites (10,000 IU/site) about 48 and 96 hours subsequently. Cycles were q2 weeks x3 then qmo x 3 (clinical trial NCT03066947). Eleven patients were treated with the above regimen in combination with a PD-1 inhibitor (pembrolizumab or INCMGA00012) (clinical trial NCT03328026). Disease response was evaluated radiographically q3 mo and as clinically indicated. Results: To estimate the tumor grade represented by the SV-BR-1-GM cell line, we developed a score we refer to as Relative Molecular Grade (RMG). SV-BR-1-GM is most similar to the MDA-MB-468 cell line (RMG of 52.1), which was classified as Basal A phenotype. Basal A cancers are less aggressive than Basal B but more aggressive than Luminal, suggesting that SV-BR-1-GM may have retained features of a grade II breast cancer. We also noted that SV-BR-1-GM expresses both Class I (HLA-A, B & C) and Class II (HLA-DR and -DP) molecules, and that the HLA-DR expression is enhanced by treatment with IFNγ. SV-BR-1-GM expressed 31 genes which are overexpressed in breast cancer, 8 cancer-testis antigens and 3 genes expressed in breast tissue. In 30 patients treated with the SV-BR-1-GM regimen (19 with the SV-BR-1-GM regimen alone, 4 who began on the SV-BR-1-GM regimen and transitioned to combination with a PD-1i, and 7 with combination therapy alone) there were 7 with grade II breast cancer and 1 with grade I breast cancer (Table). These patients were heavily pre-treated with an average of 10 prior regimens. While only one patient with grade III cancer showed disease control, 75% of the patients with grade I or II tumors showed disease control. Patients remained on study for up to 259 days.Conclusions: SV-BR-1-GM appears to retain characteristics of a moderately differentiated breast cancer, expresses multiple potential tumor antigens, and can elicit disease control especially in patients with grade I and II breast cancer.

TablePatients with Grade I/II TumorsCharacteristicSV-BR-1-GM Regimen Alone(n=6)SV-BR-1-GM Regimen + PD-1i(n=3)All Patients(n=8)Age64 ± 767 ± 465 ± 7Mean Prior Systemic Regimens6 (range 1-20)15 (range 14-15)10 (range 1-20)% ER/PR +80%100%86%% Her2/neu +0%33%14%% Triple Negative20%0%14%Delayed-type Hypersensitivity83%100%88%Disease Control Rate*67%100%75%Days on Study (Range)94 (32-181)189 (133-259)141 (32-259)•Includes CR, PR, SD (including minor responses and mixed responses)

Citation Format: William Williams, Shaker R Dakhil, Carmen Calfa, Jarrod P Holmes, Saveri Bhattacharya, Jason Lukas, Elizabeth Tan-Chiu, George E Peoples, Vivek G Sunkari, Markus D Lacher, Charles L Wiseman. Response to a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer correlates with tumor grade [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS17-20.

Association of Osteonecrosis of the Jaw With Zoledronic Acid Treatment for Bone Metastases in Patients With Cancer

Importance

Osteonecrosis of the jaw (ONJ) affects patients with cancer and metastatic bone disease (MBD) treated with bone-modifying agents (BMAs), yet the true incidence is unknown.

Objective

To define the cumulative incidence of ONJ at 3 years in patients receiving zoledronic acid for MBD from any malignant neoplasm.

Design, Setting, and Participants

This multicenter, prospective observational cohort study (SWOG Cancer Research Network S0702) included patients with MBD with either limited or no prior exposure to BMAs and a clinical care plan that included use of zoledronic acid within 30 days of registration. Medical, dental, and patient-reported outcome forms were submitted at baseline and every 6 months. Follow-up was 3 years. Osteonecrosis of the jaw was defined using established criteria. Data were collected from January 30, 2009, to December 13, 2013, and analyzed from August 24, 2018, to August 6, 2020.

Interventions/Exposures

Cancer treatments, BMAs, and dental care were administered as clinically indicated.

Main Outcomes and Measures

Cumulative incidence of confirmed ONJ, defined as an area of exposed bone in the maxillofacial region present for more than 8 weeks with no concurrent radiotherapy to the craniofacial region. Risk factors for ONJ were also examined.

Results

The SWOG S0702 trial enrolled 3491 evaluable patients (1806 women [51.7%]; median age, 63.1 [range, 2.24-93.9] years), of whom 1120 had breast cancer; 580, myeloma; 702, prostate cancer; 666, lung cancer; and 423, other neoplasm. A baseline dental examination was performed in 2263 patients (64.8%). Overall, 90 patients developed confirmed ONJ, with cumulative incidence of 0.8% (95% CI, 0.5%-1.1%) at year 1, 2.0% (95% CI, 1.5%-2.5%) at year 2, and 2.8% (95% CI, 2.3%-3.5%) at year 3; 3-year cumulative incidence was highest in patients with myeloma (4.3%; 95% CI, 2.8%-6.4%). Patients with planned zoledronic acid dosing intervals of less than 5 weeks were more likely to experience ONJ than patients with planned dosing intervals of 5 weeks or more (hazard ratio [HR], 4.65; 95% CI, 1.46-14.81; P = .009). A higher rate of ONJ was associated with fewer total number of teeth (HR, 0.51; 95% CI, 0.31-0.83; P = .006), the presence of dentures (HR, 1.83; 95% CI, 1.10-3.03; P = .02), and current smoking (HR, 2.12; 95% CI, 1.12-4.02; P = .02).

Conclusions and Relevance

As the findings show, the cumulative incidence of ONJ after 3 years was 2.8% in patients receiving zoledronic acid for MBD. Cancer type, oral health, and frequency of dosing were associated with the risk of ONJ. These data provide information to guide stratification of risk for developing ONJ in patients with MBD receiving zoledronic acid.

Abstract 5588: Clinical and pharmacodynamic responses to a modified whole tumor cell immunotherapy in patients with advanced breast cancer from two phase I-IIa trials

SV-BR-1-GM is a GM-CSF secreting breast cancer cell line that also expresses HLA class I & II antigens. Irradiated SV-BR-1-GM is used in a regimen including pre-dose low-dose cyclophosphamide and post-dose local interferon-α2b. The SV-BR-1-GM regimen has been used alone (“Monotherapy” study ClinicalTrials.gov NCT03066947) and in combination with immune checkpoint inhibitors (ongoing combination study ClinicalTrials.gov identifier NCT03328026). Here we report regression of metastatic breast cancer and pharmacodynamic analysis with immunologic correlates.

23 patients with advanced breast cancer refractory to standard therapies were treated with the SV-BR-1-GM regimen in the monotherapy trial with cycles every 2 weeks for the first month and then monthly. The combination study is evaluating the SV-BR-1-GM regimen with checkpoint inhibitors (PD-1 inhibitors pembrolizumab or INCMGA00012) with cycles every 3 weeks (11 patients have been dosed to date). Pharmacodynamic analyses include delayed-type hypersensitivity (DTH), antibodies against SV-BR-1 (precursor of SV-BR-1-GM), blood lymphocyte proliferation (determined using flow cytometry), circulating cytokines in sera and cytokine secretion (Luminex based assays) following stimulation with peptides of antigens expressed in SV-BR-1-GM cells (HER2 and PRAME).

In the monotherapy study, tumor regression was seen in 3 patients. 21 patients developed measurable DTH signifying cellular immunity. Blood lymphocytes from responders after treatment showed increased proliferation and cytokine secretion (GM-CSF, IL-2, IL-21) - following stimulation with HER2 and PRAME peptides. Differential serum cytokine levels were observed (CD40L, MCP-1, IL-1RA) in 5 patients. Increased antibody levels compared to baseline were observed in 6 of the 12 patients assessed. Patients with objective tumor regression had the most pronounced responses. In the combination therapy study, 2 patients have shown objective evidence of tumor regression, including one patient with liver metastases, which decreased by 25%, and one patient with adrenal and dural metastases (29% reduction in target lesion). Both patients had Grade II tumors, similar to the tumor from which SV-BR-1-GM was derived.

These observations confirm the ability of the SV-BR-1-GM regimen to elicit regression of far advanced refractory metastatic breast cancer. No serious toxicities clearly attributed to the SV-BR-1-GM regimen were observed. Pharmacodynamic analysis of humoral and cell-mediated immune responses showed notable upregulation, the strongest responses being seen in those with measurable clinical regression. Patients with Grade I or II tumors appeared more likely to respond.

Citation Format: Vivekananda G. Sunkari, Jacqueline Galeas, Shaker R. Dakhil, Jarrod Holmes, Saveri Bhattacharya, Carmen J. Calfa, Ajay Kundra, Daniel L. Adams, Diane DaSilva, George E. Peoples, Charles L. Wiseman, William V. Williams, Markus D. Lacher. Clinical and pharmacodynamic responses to a modified whole tumor cell immunotherapy in patients with advanced breast cancer from two phase I-IIa trials [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5588.

Randomized Trial of Text Messaging to Reduce Early Discontinuation of Adjuvant Aromatase Inhibitor Therapy in Women With Early-Stage Breast Cancer: SWOG S1105

PURPOSE

Nonadherence to aromatase inhibitors (AIs) for breast cancer is common and increases the risk of recurrence. Text messaging increases adherence to medications for chronic conditions.

METHODS

We conducted a randomized clinical trial of text messaging (TM) versus no text messaging (No-TM) at 40 sites in the United States. Eligible patients were postmenopausal women with early-stage breast cancer taking an AI for > 30 days with a planned duration of ≥ 36 months. Test messages were sent twice a week over 36 months. Content themes focused on overcoming barriers to medication adherence and included cues to action, statements related to medication efficacy, and reinforcements of the recommendation to take AIs. Both groups were assessed every 3 months. The primary outcome was time to adherence failure (AF), where AF was defined as urine AI metabolite assay results satisfying one of the following: < 10 ng/mL, undetectable, or no submitted specimen. A stratified log-rank test was conducted. Multiple sensitivity analyses were performed.

RESULTS

In total, 724 patients were registered between May 2012 and September 2013, among whom,702 patients (348 in the text-messaging arm and 354 in the no-text-messaging arm) were eligible at baseline. Observed adherence at 36 months was 55.5% for TM and 55.4% for No-TM. The primary analysis showed no difference in time to AF by arm (3-year AF: 81.9% TM v 85.6% No-TM; HR, 0.89 [95% CI, 0.76 to 1.05]; P = .18). Multiple time to AF sensitivity analyses showed similar nonsignificant results. Three-year self-reported time to AF (10.4% v 10.3%; HR, 1.16 [95% CI, 0.69 to 1.98]; P = .57) and site-reported time to AF (21.9% v 18.9%; HR, 1.31 [95% CI, 0.86 to 2.01]; P = .21) also did not differ by arm.

CONCLUSION

To our knowledge, this was the first large, long-term, randomized trial of an intervention directed at improving AI adherence. We found high rates of AI AF. Twice-weekly text reminders did not improve adherence to AIs. Improving long-term adherence will likely require personalized and sustained behavioral interventions.

Liquid biopsy: A community-based oncology practice experience

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Background: Liquid biopsy is a promising and minimally invasive genetic test examining plasma circulating tumor DNA. Coupled with the rapidly developing next-generation sequencing (NGS) technologies, it holds the potential for implementation in selecting signal-matched therapeutic options. Methods: A retrospective chart review was conducted on adult patients with advanced solid tumors whose tumors were tested with Guardant360 assay, between December 2018 and December 2019. A total of 178 patients were referred for testing by 12 oncologists within a single community cancer center. Results: Referral rates varied widely (2.25% - 22%). The majority of patients (98%) were tested upfront for molecular marker evaluation, in either newly diagnosed advanced cancer patients, or in recurrent patients without enough tissue for testing. Other patients (2%) were evaluated after failure of 1 st line therapy to assess for acquired mutations. A total of 18 histological types were tested, with lung (LCa; n = 90; 50.56%), breast (BCa; n = 31; 17.42%), and colorectal (CRCa; n = 14; 7.87%) cancers being the most common types. In 86.11% of all tests (n = 180), ≥ 1 alteration was detected, while 13.89 % of tests did not reveal any tumor-related mutation, and were considered negative. The average number of alterations per test was 3.1 (±2.14; n = 481), and varied across types: CRCa (4.36), prostate cancer (2.73), BCa (2.97), and LCa (2.59), had the highest average number of alterations per test. Similarly, LCa (48.44%), BCa (19.13%), and CRCa (12.68%), harbored most of the detected somatic alterations (n = 481). Of all the alterations of practical significance (n = 457), TP53 (32.17%), PIK3CA (8.53%), EGFR (7.66%) and KRAS (7.22%), were the most commonly altered genes. Only 1 patient had a positive MSI-H status, amenable to immune-therapy. Of those with positive test results (n = 155), 31 (20%) had ≥ 1 FDA approved, target-matched therapeutic opportunity. Similarly, 71 patients (45.81%) had ≥ 1 target-matched therapeutic opportunity, outside current indications. Lastly, when no FDA-approved target-matched therapy was available (n = 39), results from liquid biopsy testing offered signal-based clinical trial opportunity in 39/39 patients. Conclusions: Implementation of NGS-based liquid biopsy testing is feasible within a community practice. In the era of precision oncology, such assays have the potential to expedite the efforts towards target-matched therapies and signal-based clinical trial opportunities. Further studies are warranted to identify the most-cost effective testing strategies.

Breast cancer grade and clinical benefit in patients with advanced breast cancer treated with an engineered whole tumor cell-targeted immunotherapy alone or in combination with checkpoint inhibition

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Background: SV-BR-1 is a breast cancer cell line derived from a grade II (moderately differentiated) tumor. SV-BR-1 was transfected with the CSF2 gene (encoding GM-CSF) to form SV-BR-1-GM. SV-BR-1-GM expresses HLA class I & II antigens and has functional antigen-presenting cell activity, directly stimulating CD4+ T cells in an HLA-DR restricted fashion. The SV-BR-1-GM regimen consists of low-dose cyclophosphamide (300 mg/m2) to reduce immune suppression, intradermal inoculation with irradiated SV-BR-1-GM (20x106 cells divided into 4 sites) and interferon-α2b (10,000 IU into each inoculation site ~2 & 4 days later) to boost the response. Here, we evaluate the impact of tumor grade on clinical benefit following treatment with the SV-BR-1-GM regimen. Methods: Patients with advanced breast cancer were treated with either the SV-BR-1-GM regimen alone or with the SV-BR-1-GM regimen with pembrolizumab. For the SV-BR-1-GM regimen alone, cycles were administered every 2 weeks x 3 and then monthly, while combination with pembrolizumab (200 mg IV 1-5 days following SV-BR-1-GM inoculation) administered cycles every 3 weeks. Tumor restaging was every 6-12 weeks. Results: 33 patients were enrolled. The treatment was generally safe with inoculation site pruritis, erythema and induration the most common adverse events. 23 patients had grade III (poorly differentiated) tumors, 9 had grade II tumors and one had a grade I (well differentiated) tumor. None of the patients with grade III tumors exhibited clinical benefit. 7 patients with grade I/II tumors received the SV-BR-1-GM regimen alone, 2 received the SV-BR-1-GM regimen with pembrolizumab and 1 received both regimens. As noted in the Table, 7 patients experienced clinical benefit including all 3 patients treated in combination with pembrolizumab. This included 6 patients with stable disease and one with a partial response. Conclusions: The SV-BR-1-GM regimen with or without pembrolizumab appears safe and able to induce clinical benefit even in very heavily pre-treated patients with low or intermediate grade advanced breast cancer. Clinical trial information: NCT03328026 . [Table: see text]

Clinical outcomes in patients with BRAFV600 mutant melanoma and undetectable circulating tumor DNA treated with dabrafenib and trametinib

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Background: Circulating tumor DNA (ctDNA) analysis has been promoted as a less-invasive surrogate assay for tumor-tissue based tumor oncogene analysis. Here, we associate detection of BRAF mutant ctDNA with PFS and OS in patients with tissue-confirmed BRAFV600 mutant melanoma enrolled in S1320, a randomized phase 2 clinical trial of continuous versus intermittent dosing of dabrafenib and trametinib. Methods: Patients with BRAFV600 melanoma received continuous therapy with dabrafenib and trametinib for 8 weeks after which patients were randomized 1:1 to proceed with intermittent treatment on a 3-week-off, 5-week-on schedule or to continue with continuous therapy. Pre-treatment blood samples were interrogated using the Guardant 360 ctDNA assay for all exons of 30 known oncogenes including BRAF and for all exons with known oncogenic mutations in the COSMIC database in 40 additional oncogenes. Clinical responses were assessed at 8-week intervals by RECIST v1.1 and PFS and OS estimates were compared using log-rank test in patients with detectable versus undetectable BRAFV600 mutant ctDNA,. Results: Somatic BRAFV600E or BRAFV600K ctDNA was detected in 34 of 50 patients with baseline (before lead-in cycle 1) blood samples available for analysis including 16 of 23 (70%) patients randomized to continuous dosing, 15 of 21 (71%) randomized to intermittent dosing, and 3 of 6 (50%) who were not randomized due to disease progression at 8 weeks or other factors. Four additional patients had other detectable somatic mutations but no detectable BRAFV600 ctDNA at baseline, and 12 patients had no detectable somatic ctDNA mutations at baseline. Detection of BRAFV600 ctDNA was associated with baseline disease stage (p = 0.008). There was no difference in the overall response rate based on baseline ctDNA detection. Detection of ctDNA at baseline was associated with worse PFS (median BRAFV600 ctDNA positive = 5.8; 95% CI: 4.2-9.6 months, BRAFV600 ctDNA negative = 21.4 mos; 95% CI 10.4-NA; measured from registration to lead-in cycle 1, p = 0.001) and OS (BRAFV600 ctDNA positive = 17.8 mos; 95% CI 9.76-NA, BRAFV600 ctDNA negative = not reached; 95% CI NA-NA, p = 0.0021). Conclusions: The absence of detectable BRAFV600 ctDNA at baseline is associated with improved PFS and OS in patients receiving treatment with dabrafenib and trametinib. Clinical trial information: NCT02196181.

Final Analysis of the Prevention of Early Menopause Study (POEMS)/SWOG Intergroup S0230

Premature menopause is a serious long-term side effect of chemotherapy. We evaluated long-term pregnancy and disease-related outcomes for patients in S0230/POEMS, a study in premenopausal women with stage I-IIIA estrogen receptor-negative, progesterone receptor-negative breast cancer to be treated with cyclophosphamide-containing chemotherapy. Women were randomly assigned to standard chemotherapy with or without goserelin, a gonadotropin-releasing hormone agonist, and were stratified by age and chemotherapy regimen. All statistical tests were two-sided. Of 257 patients, 218 were eligible and evaluable (105 in the chemotherapy + goserelin arm and 113 in the chemotherapy arm). More patients in the chemotherapy + goserelin arm reported at least one pregnancy vs the chemotherapy arm (5-year cumulative incidence = 23.1%, 95% confidence interval [CI] = 15.3% to 31.9%; and 12.2%, 95% CI = 6.8% to 19.2%, respectively; odds ratio = 2.34; 95% CI = 1.07 to 5.11; P = .03). Randomization to goserelin + chemotherapy was associated with a nonstatistically significant improvement in disease-free survival (hazard ratio [HR] = 0.55; 95% CI = 0.27 to 1.10; P = .09) and overall survival (HR = 0.45; 95% CI = 0.19 to 1.04; P = .06). In this long-term analysis of POEMS/S0230, we found continued evidence that patients randomly assigned to receive goserelin + chemotherapy were not only more likely to avoid premature menopause, but were also more likely to become pregnant without adverse effect on disease-related outcomes.

Dual VEGF inhibition with sorafenib and bevacizumab as salvage therapy in metastatic colorectal cancer: results of the phase II North Central Cancer Treatment Group study N054C (Alliance)

Background

Bevacizumab (BEV), a monoclonal antibody against vascular endothelial growth factor-A (VEGF-A), is a standard component of medical therapy of metastatic colorectal cancer (mCRC). Activation of alternative angiogenesis pathways has been implicated in resistance to BEV. This phase II study examines the activity of combined vertical blockade of VEGF signaling with sorafenib and BEV as salvage therapy in patients with progressive disease (PD) on all standard therapy in mCRC.

Methods

mCRC patients with documented PD on standard therapy, received sorafenib (200 mg orally twice daily, days 1-5 and 8-12) and BEV (5 mg/kg intravenously, day 1) every 2 weeks. Primary endpoint was 3-month progression-free survival (PFS) rate and secondary endpoints were overall survival (OS), response rate (RR), safety, and feasibility.

Results

Of the 83 patients enrolled, 79 were evaluable. Of these, 42 (53%) were progression-free at 3 months. Median PFS was 3.5 months and median OS was 8.3 months. One patient had a partial response and 50 patients (63.3%) had at least one stable tumor assessment. Of 79 evaluable patients, 54 (68%) experienced grade 3/4 adverse events (AEs) at least possibly related to treatment. Most frequent grade 3/4 AEs were: fatigue (24.1%), hypertension (16.5%), elevated lipase (8.9%), hand-foot skin reaction (8.9%), diarrhea (7.6%), and proteinuria (7.6%). Reasons for treatment discontinuation were PD (72%), AEs (18%), patient refusal (8%), physician decision (1%), and death (1%).

Conclusions

The combination of BEV and sorafenib as salvage therapy in heavily pretreated mCRC patients is tolerable and manageable, with evidence of promising activity.

ClinicalTrialsgov identifier

NCT00826540, URL:http://clinicaltrials.gov/ct2/show/NCT00826540.

Abstract P3-09-08: Efficacy and safety of a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer alone and in combination with immune checkpoint inhibitors

Background: SV-BR-1-GM is a GM-CSF transfected breast cancer cell line, exceptional for having antigen-presenting capability expressing both HLA I and II. We report clinical efficacy, safety, and immunologic correlates of response from our initial Phase I/II trial and initial data from our trial of SV-BR1-GM in combination with immune checkpoint inhibitors. Methods: We enrolled patients with recurrent and/or metastatic breast cancer refractory to standard therapy. Patients received cyclophosphamide 300 mg/m2 2-3d prior to intradermal injection of SV-BR-1-GM (20-40 × 106 cells divided into 4 sites) and IFNα into the inoculation sites (10,000 IU/site) ~2 & 4 days subsequently. Cycles were q2 weeks x3 then qmo x 3. Adverse events (AE) were evaluated after each inoculation. Immunologic responses were measured by delayed type hypersensitivity (DTH) after each inoculation with humoral and cellular responses evaluated ~q3 mo. Disease response was evaluated radiographically q3 mo and as clinically indicated (clinical trial NCT03066947). A similar regimen was used with SV-BR-1-GM in combination with pembrolizumab (200 mg IV) with cycles every 3 weeks (Phase I/II study NCT03328026). Results: In Phase I/IIa (NCT03066947), 23 patients underwent 1 - 8 cycles of treatment. Tumor regression was seen in 3 patients, all of whom matched SV-BR-1-GM at least at one HLA allele. There were no related serious adverse events. The most common adverse event was minor local irritation at the inoculation site. Clinical data are shown in the table. A measurable DTH response was present in 21 patients. Of patients who developed a DTH response and had at least one HLA match, the tumor regression rate was 33% and for those with 2 HLA matches 67%. We saw evidence of antibody responses in 3 of 5 patients evaluated to date. Especially in responders after treatment, blood lymphocytes showed increased cytokine secretion (including ITAC, IFNγ, IL-6 & IL-8) following stimulation with antigens expressed in SV-BR-1-GM. 21/23 patients had expression of PD-L1 in identified circulating cancer-associated cells, and expression levels increased with treatment. Therefore, a combination study with pembrolizumab was initiated. Data on the first 6 patients shows that the regimen is clinically active and safe. One patient with a robust DTH response had evidence of tumor regression in liver metastases. This study is ongoing and is being modified to evaluate combination therapy with the PD-1 inhibitor INCMGA00012 and the IDO inhibitor epacadostat. Conclusions: SV-BR-1-GM appears to be safe and well-tolerated. Contrary to conventional wisdom, SV-BR-1-GM can produce regression of metastatic breast cancer correlating with an immunologic response and HLA matching. Combination therapy with checkpoint inhibitors is ongoing.

Citation Format: William Williams, Shaker R Dakhil, Jarrod P Holmes, Saveri Bhattacharya, Carmen Calfa, Ajay Kundra, Daniel L Adams, Diane DaSilva, George E Peoples, Vivek Sunkari, Markus Lacher, Charles L Wiseman. Efficacy and safety of a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer alone and in combination with immune checkpoint inhibitors [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-09-08.

Irinotecan, cetuximab, and bevacizumab (CBI) versus irinotecan, cetuximab, and placebo (CI) in irinotecan-refractory metastatic colorectal cancer (mCRC): Results from an ACCRU network randomized phase II trial

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Background: Combination irinotecan and cetuximab is approved for irinotecan-refractory mCRC; it is unknown if the addition of bevacizumab would improve outcomes. We studied the efficacy and safety of CBI compared with CI in patients (pts) with RAS wildtype, irinotecan-refractory mCRC. Methods: In this multicenter, randomized, double-blind, placebo-controlled phase II trial, pts with RAS wildtype mCRC and no prior anti-epidermal growth factor receptor therapy who failed at least 1 irinotecan-based chemotherapy regimen and received bevacizumab in at least 1 prior line of therapy were randomized 1:1 to irinotecan 180 mg/m2 (or previously tolerated dose), cetuximab 500 mg/m2, and bevacizumab 5 mg/kg vs CI every 2 wks until disease progression, intolerable toxicity, or withdrawal of consent. The primary endpoint was progression free survival (PFS). Multivariable Cox proportional hazard models stratified by number of prior lines of therapy and bevacizumab receipt in immediate prior line were performed. Secondary endpoints included overall survival (OS), objective response rate (ORR), and adverse events (AEs). The study was closed early in January 2018 for reasons related to accrual and funding after enrollment of 36 out of a planned 60 pts. Results: Between July 2015 and December 2017, 36 pts were randomized (19 to CBI, 17 to CI). 34 pts (94%) were treated with 2 or more prior chemotherapy regimens. Baseline characteristics were similar between arms. Median PFS was 9.7 vs 5.5 mo for CBI and CI arms, respectively (log-rank P =0.76; multivariable HR = 0.64; 95% CI, 0.25-1.66). Median OS was 19.7 vs 10.2 mo for CBI and CI (log-rank P= 0.04; multivariable HR = 0.41; 95% CI, 0.15-1.09). ORR was 37% for CBI vs 12% for CI ( P =0.13). Grade 3 or higher AEs occurred in 47% of pts receiving CBI vs 35% for CI ( P =0.46). Conclusions: In this prematurely discontinued trial, there were non-significant increases in PFS and ORR and a statistically significant 9.5 mo increase in median OS in favor of CBI compared to CI. Further investigation of CBI for treatment of irinotecan-refractory mCRC is warranted. Clinical trial information: NCT02292758.

A Randomized Double-Blind Phase II Study of the Seneca Valley Virus (NTX-010) versus Placebo for Patients with Extensive-Stage SCLC (ES SCLC) Who Were Stable or Responding after at Least Four Cycles of Platinum-Based Chemotherapy: North Central Cancer Treatment Group (Alliance) N0923 Study

INTRODUCTION

The Seneca Valley virus (NTX-010) is an oncolytic picornavirus with tropism for SCLC. This phase II double-blind, placebo-controlled trial evaluated NTX-010 in patients with extensive-stage (ES) SCLC after completion of first-line chemotherapy.

METHODS

Patients with ES SCLC who did not progress after four or more cycles of platinum-based chemotherapy were randomized 1:1 to a single dose of NTX-010 or placebo within 12 weeks of chemotherapy. The primary end point was progression-free survival (PFS). A prespecified interim analysis for futility was performed after 40 events. Viral clearance and the development of neutralizing antibodies were followed.

RESULTS

From January 15, 2010, to January 10, 2013, a total of 50 patients were randomized and received therapy on study (26 received NTX-010 and 24 received placebo). At the specified interim analysis, the median PFS was 1.7 months (95% confidence interval [CI]: 1.4-3.1 months) for the NTX-010 group versus 1.7 months (95% CI: 1.4-4.3 months) for the placebo group (hazard ratio = 1.03, p = 0.92), and the trial was terminated owing to futility. In the NTX-010 group, PFS was shorter in patients with detectable virus at days 7 and 14 versus in those in whom it was not detected after treatment (1.0 month [95% CI: 0.4-1.5 months] versus 1.8 months [95% CI: 1.3-5.5 months, p = 0.008] and 0.9 months [95% CI: 0.4-2.6 months] versus 1.3 months [95% CI: 1.0-5.3 months], respectively [p = 0.04]).

CONCLUSIONS

Patients with ES SCLC did not benefit from NTX-010 treatment after chemotherapy with a platinum doublet. Persistence of NTX-010 in the blood 1 or 2 weeks after treatment was associated with a shorter PFS.

Rates of deep molecular response by digital and conventional PCR with frontline nilotinib in newly diagnosed chronic myeloid leukemia: a landmark analysis

ENESTnext (NCT01227577) was a single-arm, multicenter trial evaluating the rate of deep molecular response by 2 years in patients with newly diagnosed (within 6 months) chronic myeloid leukemia in chronic phase (CML-CP) treated with nilotinib 300 mg twice daily. Among 128 enrolled patients, 94 (73%) achieved major molecular response (MMR; BCR-ABL1 ≤ 0.1% on the International Scale [BCR-ABL1IS]) and 34 (27%) achieved confirmed MR4.5 (BCR-ABL1IS ≤0.0032% detectable or undetectable; primary endpoint) by 2 years. Three-month BCR-ABL1 levels were predictive of later responses. In exploratory analyses, digital polymerase chain reaction (PCR) detected BCR-ABL1 in 39.4% of samples from patients with confirmed MR4.5 and identified further decreases in BCR-ABL1 with continued nilotinib. Safety results, including cardiovascular events, were consistent with those in other nilotinib trials. These results further substantiate the molecular response rates associated with frontline nilotinib therapy and demonstrate the feasibility of monitoring very low BCR-ABL1 transcript levels using digital PCR.

Antigen (Ag) spread after sipuleucel-T and correlation with overall survival (OS): A real-world experience

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Background: Sipuleucel-T is an autologous cellular immunotherapy for asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer. In IMPACT (NCT00065442), a phase 3 trial, sipuleucel-T-induced immune responses against target Ag prostatic acid phosphatase (PAP) or PA2024, a recombinant protein consisting of PAP and granulocyte macrophage colony stimulating factor, correlated with OS (Sheikh 2013). Additionally, sipuleucel-T-induced immunoglobulin G (IgG) responses against secondary, non-target Ag (i.e. Ag spread) and the breadth of Ag spread also correlated with improved OS (GuhaThakurta 2015). Here we assessed Ag spread and OS in real-world patients from PRIME (NCT01727154), an immune monitoring sub-study of sipuleucel-T trials Methods: IgG levels in pre and wk 6 (2 wk post sipuleucel-T completion) sera from PRIME (n = 100) were quantified using Luminex xMAP. IgG responses to secondary Ag (LGALS3, PSA, KLK2, LGALS8, K-Ras, E-Ras) were defined as ≥ 1.5-fold increase over baseline. OS associations with individual Ag responses and total number of Ag per patient were assessed using the Kaplan-Meier method. Hazard ratios (HR) were estimated using a Cox Proportional Hazard Model. Results: IgG responses to ≥1 secondary Ag were observed in ≥72% of patients. Individual IgG responses to LGALS3, K-Ras, and LGALS8 at wk 6 were significantly associated with OS. Furthermore, breadth of Ag spread positively correlated with OS (Table); as the total number of Ag responses per patient increased, OS improved compared to patients with no secondary IgG responses. Conclusions: The results presented are consistent with findings from the prior phase 3 trial IMPACT. Secondary Ag responses were generated in real-world patients treated with sipuleucel-T, and these responses correlated with OS. Furthermore, breadth of Ag spread also correlated with improved OS. Clinical trial information: NCT01727154. [Table: see text]

Randomized trial of text messaging (TM) to reduce early discontinuation of aromatase inhibitor (AI) therapy in women with breast cancer: SWOG S1105

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Background: Non-adherence to AI’s for breast cancer is common and increases risk of recurrence. Text messaging (TM) has been shown to increase adherence to medications for chronic conditions. We conducted a multicenter randomized trial to evaluate if TM reminders improve AI adherence. Methods: Patients taking an AI for ≥30 days and having ≥36 mos of planned therapy were eligible. Patients were randomly assigned 1:1 to receive either TM or NO-TM twice a week for 36 mos. Randomization was stratified by length of time on prior AI therapy ( < 12 (64%) vs. 12-24 mos (36%)) and AI class (anastrozole, letrozole, exemestane). Content themes of the 36 TMs focused on overcoming barriers to adherence. Patients were assessed for discontinuation of AIs every 3 mos for 36 mos. The primary outcome was time to non-adherence, where non-adherence was defined as urine AI metabolite assay results satisfying the following: < 10 [units], undetectable, or no submitted specimen. A stratified Log-rank test was conducted. Multiple sensitivity analyses were performed using Cox regression. Results: In total, 724 patients were registered between May, 2012 and September, 2013, among whom 696 (338/360 (93.9%) on TM and 338/364 (92.9%) on NO-TM) were eligible and adherent at baseline. Observed (time-independent) adherence at 36 mos was 55.4% for TM and 55.4% for NO-TM. The primary analysis showed no difference in time-to-adherence failure between patients on the TM and NO-TM arms (HR = 0.89, 95% CI:0.76,1.05 p = .18). An analysis of negative urine tests alone resulted in similar non-significant results. With missed appointments not counted as failures, time to self-reported discontinuation (89.6% vs. 89.7%; HR = 1.17, 95% CI:0.69-1.98, p = .57) and site reported discontinuation (78.1% vs. 81.1%; HR = 1.31, 95% CI:0.86-2.01, p = .21) were also similar between the 2 groups. Conclusions: As the first large long-term randomized trial of an intervention directed at improving AI adherence, we found high rates of AI discontinuation. Bi-weekly text reminders did not improve adherence to AIs compared to usual care. Improving long—term adherence will likely require sustained behavioral interventions and support. Clinical trial information: NCT01515800.

Safety and efficacy of a phase I/IIa trial (NCT03066947) of a modified whole tumor cell targeted immunotherapy in patients with advanced breast cancer

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Background: SV-BR-1-GM is a GM-CSF transfected breast cancer cell line which expresses HLA class I & II antigens and has functional antigen-presenting cell activity. Prior studies suggest that partial matching of the HLA type of the patient with SV-BR-1-GM may be predictive of tumor regression. Methods: Subjects received low-dose cyclophosphamide 2-3d prior to ID injection of irradiated SV-BR-1-GM (20 million cells divided into 4 sites) and interferon-α into the inoculation sites ~2 & 4 days subsequently. Cycles were q2 weeks x 3 then q mo. Results: A total of 30 patients were screened and 23 inoculated (Table). The patients were heavily pretreated with a median of 4 prior chemo/biological therapy regimens. There were no serious or unexpected adverse events. Local injection-site irritation was the most common toxicity. Objective tumor regression was seen in 3 patients, all of whom matched SV-BR-1-GM at least at one HLA locus: one patient with regression or clearing of 20 lung metastases; one with reduction in cutaneous involvement of the breast from 80% to 30% and one with regression of a breast lesion. Another 3 patients had decreases in circulating cancer-associated macrophage-like cells (CAMLs), which has been shown to correlate with tumor stage. They also all matched at least at one HLA allele. Circulating tumor cells and circulating epithelial cells were present in low numbers and tended to parallel trends in CAMLs which were present in larger numbers. CAMLs in 21/23 patients stained positive for PD-L1. Patients with tumor regression had robust DTH responses to SV-BR-1-GM. Conclusions: SV-BR-1-GM in this regimen appears to be safe and well-tolerated and is associated with objective regression of metastatic breast cancer and/or with decreases in circulating cancer-associated cells in 6/23 (26%) or patients. HLA matching may be a predictor of response. Clinical trial information: NCT03066947. [Table: see text]

Osteonecrosis of the jaw in patients with cancer receiving zoledronic acid for bone metastases: SWOG S0702, NCT00874211

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Background: Osteonecrosis of the jaw (ONJ) may occur in cancer patients (pts) with metastatic bone disease (MBD) treated with bone modifying agents. No large prospective studies have precisely determined the incidence of ONJ. A better understanding of the true incidence and predictors of ONJ is needed. Methods: SWOG S0702 was a prospective observational study that assessed the cumulative incidence (CI) of ONJ at 3 years in pts with MBD from any malignancy receiving zoledronic acid (Zol). Participants must have had either limited or no prior exposure to bone modifying agents and a clinical care plan that included use of Zol within 30 days of registration. Cancer treatments, bone modifying agents (including Zol), and dental care were administered as clinically indicated and were not directed by S0702. Baseline and every 6 m followup dental exams were recommended. Report forms (medical, dental and pt reported outcomes) were submitted every 6 m but if ONJ was diagnosed, follow up interval became every 3 m. Protocol defined ONJ required exposed bone in the maxillofacial region present 8 weeks or more in a pt who was receiving or had been exposed to a bisphosphonate, and had not had radiation therapy to the craniofacial region. Results: The study enrolled 3,491 evaluable pts (breast 1,120; myeloma 580; prostate 702, lung 666, other 423) between 2009-2013. About 2/3 of pts had a baseline dental exam. Overall, 87 pts had confirmed ONJ. The cumulative incidence of ONJ was 0.8% at year 1 (95% CI: 0.5%-1.1%), 2.0% at year 2 (95% CI: 1.5%-2.5%), and 2.8% at year 3 (95% CI: 2.3-3.5%). Rates of 3-year confirmed ONJ were highest in myeloma pts (4.3%; 95% CI, 2.8%-6.4%). Pts with planned Zol dosing intervals of every 3-4 weeks (n = 3,032, 87.2%) were much more likely to experience ONJ than pts with planned dosing intervals of 5 weeks or greater (n = 447, 12.8%; 3.2% vs 0.7%; HR = 4.80, 95% CI, 1.52-15.18, p = .008). Fewer total number of teeth, the presence of dentures and any oral surgery at baseline were all associated with a higher rate of ONJ. Conclusions: About 1 in 40 patients receiving Zol for MBD developed ONJ. S0702 provides information to guide stratification of risk for developing ONJ in pts with MBD receiving Zol. Cancer type, oral health and frequency of Zol dosing affect risk of ONJ. Clinical trial information: NCT00874211.

Overall Survival with Fulvestrant plus Anastrozole in Metastatic Breast Cancer

BACKGROUND

We previously reported prolonged progression-free survival and marginally prolonged overall survival among postmenopausal patients with hormone receptor-positive metastatic breast cancer who had been randomly assigned to receive the aromatase inhibitor anastrozole plus the selective estrogen-receptor down-regulator fulvestrant, as compared with anastrozole alone, as first-line therapy. We now report final survival outcomes.

METHODS

We randomly assigned patients to receive either anastrozole or fulvestrant plus anastrozole. Randomization was stratified according to adjuvant tamoxifen use. Analysis of survival was performed by means of two-sided stratified log-rank tests and Cox regression. Efficacy and safety were compared between the two groups, both overall and in subgroups.

RESULTS

Of 707 patients who had undergone randomization, 694 had data available for analysis. The combination-therapy group had 247 deaths among 349 women (71%) and a median overall survival of 49.8 months, as compared with 261 deaths among 345 women (76%) and a median overall survival of 42.0 months in the anastrozole-alone group, a significant difference (hazard ratio for death, 0.82; 95% confidence interval [CI], 0.69 to 0.98; P = 0.03 by the log-rank test). In a subgroup analysis of the two strata, overall survival among women who had not received tamoxifen previously was longer with the combination therapy than with anastrozole alone (median, 52.2 months and 40.3 months, respectively; hazard ratio, 0.73; 95% CI, 0.58 to 0.92); among women who had received tamoxifen previously, overall survival was similar in the two groups (median, 48.2 months and 43.5 months, respectively; hazard ratio, 0.97; 95% CI, 0.74 to 1.27) (P = 0.09 for interaction). The incidence of long-term toxic effects of grade 3 to 5 was similar in the two groups. Approximately 45% of the patients in the anastrozole-alone group crossed over to receive fulvestrant.

CONCLUSIONS

The addition of fulvestrant to anastrozole was associated with increased long-term survival as compared with anastrozole alone, despite substantial crossover to fulvestrant after progression during therapy with anastrozole alone. The results suggest that the benefit was particularly notable in patients without previous exposure to adjuvant endocrine therapy. (Funded by the National Cancer Institute and AstraZeneca; ClinicalTrials.gov number, NCT00075764.).

Real-world PROCEED registry data: Sipuleucel-T in elderly men with metastatic castration-resistant prostate cancer (mCRPC)

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Background: Managing patients ≥ 80 years old (yo) with mCRPC is challenging, given the high prevalence of comorbidities, polypharmacy, organ dysfunction, and reduced performance status (PS). Balancing treatment benefit with safety and quality of life is particularly germane for this group. Sipuleucel-T, an autologous cellular immunotherapy for mCRPC, is generally well-tolerated. Prior analyses from PROCEED, a large registry for sipuleucel-T in men with mCRPC, demonstrated that upregulation of immune cells in these elderly patients is similar to that of younger men. Here, we report on this clinical experience. Methods: PROCEED enrolled men with mCRPC treated with sipuleucel-T given every 2 weeks x 3, with no dose adjustment for organ dysfunction or drug interactions. The elderly cohort included those ≥ 80 yo. Men were followed until death, study withdrawal, or a minimum of 3 years. Results: Of 1902 patients who received ≥1 sipuleucel-T infusion, 374 (19.7%) were ≥ 80 yo. Compared to men < 80 yo (Table), this cohort was 14 years older, had worse Eastern Cooperative Oncology Group (ECOG) PS and higher prostate-specific antigen (PSA) at baseline. All grade (16.3% elderly v. 13.7% younger) and grade 3-5 (10.7% elderly v. 9.9% younger) serious adverse events were comparable between groups. However, the median overall survival (OS) of elderly men was 10.7 mo shorter than that of younger men (< 80 yo). Conclusions: Sipuleucel-T was generally well-tolerated in those ≥ 80 yo in a real-world setting and may be considered a first-line option for the elderly with asymptomatic or minimally symptomatic mCRPC. As expected, OS was shorter than in younger patients. Clinical trial information: NCT01306890. [Table: see text]

Experience with sipuleucel-T in metastatic castration-resistant prostate cancer (mCRPC) with visceral spread from PROCEED

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Background: Trials of approved agents in mCRPC have reported shorter overall survival (OS) in men with visceral metastases (mets). The phase 3 IMPACT trial evaluated sipuleucel-T, an autologous cellular immunotherapy, in mCRPC but excluded visceral mets. PROCEED, a registry of mCRPC patients receiving sipuleucel-T, offers the first description of sipuleucel-T in patients with visceral mets. Methods: PROCEED enrolled men with mCRPC treated with sipuleucel-T biweekly x 3. Dose adjustment for organ dysfunction was unnecessary. Men were followed until death, study withdrawal, or a minimum of 3 years. OS is reported in this post-hoc subgroup analysis. Results: 1902 men received ≥1 sipuleucel-T infusion between 2011-2014. Visceral mets (n = 90) included liver (n=21), lung (n=61), and brain (n=2) involvement. Compared to patients without visceral mets (Table), men with visceral mets had poorer performance status (PS) and higher baseline prostate-specific antigen (PSA). Median OS was 20.5 and 31.2 mo in those with and without visceral mets. Patients with liver and lung mets had a median OS of 16.3 and 21.0 mo, respectively. Activation of antigen-presenting cells, a measure of immune activation and product potency, was similar in those with and without visceral mets. Conclusions: Initial observations suggest that patients with mCRPC and visceral spread can activate their immune cells to produce sipuleucel-T, but have a shorter OS than those with bone and/or lymph node spread. (NCT01306890). Clinical trial information: NCT00065442. [Table: see text]

Use of letrozole after aromatase inhibitor-based therapy in postmenopausal breast cancer (NRG Oncology/NSABP B-42): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

The optimal duration of extended therapy with aromatase inhibitors in patients with postmenopausal breast cancer is unknown. In the NSABP B-42 study, we aimed to determine whether extended letrozole treatment improves disease-free survival after 5 years of aromatase inhibitor-based therapy in women with postmenopausal breast cancer.

METHODS

This randomised, double-blind, placebo-controlled, phase 3 trial was done in 158 centres in the USA, Canada, and Ireland. Postmenopausal women with stage I-IIIA hormone receptor-positive breast cancer, who were disease-free after about 5 years of treatment with an aromatase inhibitor or tamoxifen followed by an aromatase inhibitor, were randomly assigned (1:1) to receive 5 years of letrozole (2·5 mg orally per day) or placebo. Randomisation was stratified by pathological node status, previous tamoxifen use, and lowest bone mineral density T score in the lumbosacral spine, total hip, or femoral neck. The primary endpoint was disease-free survival, defined as time from randomisation to breast cancer recurrence, second primary malignancy, or death, and was analysed by intention to treat. To adjust for previous interim analyses, the two-sided statistical significance level for disease-free survival was set at 0·0418. This study is registered with ClinicalTrials.gov, number NCT00382070, is active, and is no longer enrolling patients.

FINDINGS

Between Sept 28, 2006, and Jan 6, 2010, 3966 patients were randomly assigned to receive letrozole (n=1983) or placebo (n=1983). Follow-up information was available for 3903 patients for the analyses of disease-free survival. Median follow-up was 6·9 years (IQR 6·1-7·5). Letrozole treatment did not significantly improve disease-free survival (339 disease-free survival events were reported in the placebo group and 292 disease-free survival events were reported in the letrozole group; hazard ratio 0·85, 95% CI 0·73-0·999; p=0·048). 7-year disease-free survival estimate was 81·3% (95% CI 79·3-83·1) in the placebo group and 84·7% (82·9-86·4) in the letrozole group. The most common grade 3 adverse events were arthralgia (47 [2%] of 1933 patients in the placebo group vs 50 [3%] of 1941 patients in the letrozole group) and back pain (44 [2%] vs 38 [2%]). The most common grade 4 adverse event in the placebo group was thromboembolic event (eight [<1%]) and the most common grade 4 adverse events in the letrozole group were urinary tract infection, hypokalaemia, and left ventricular systolic dysfunction (four [<1%] each).

INTERPRETATION

After 5 years of aromatase inhibitor-based therapy, 5 years of letrozole therapy did not significantly prolong disease-free survival compared with placebo. Careful assessment of potential risks and benefits is required before recommending extended letrozole therapy to patients with early-stage breast cancer.

FUNDING

National Cancer Institute, Korea Health Technology R&D Project, Novartis.

Longitudinal Trajectory and Characterization of Cancer-Related Cognitive Impairment in a Nationwide Cohort Study

PURPOSE

Cancer-related cognitive impairment (CRCI) is an important clinical problem in patients with breast cancer receiving chemotherapy. Nationwide longitudinal studies are needed to understand the trajectory and severity of CRCI in specific cognitive domains.

PATIENTS AND METHODS

The overall objective of this nationwide, prospective, observational study conducted within the National Cancer Institute Community Clinical Oncology Research Program was to assess trajectories in specific cognitive domains in patients with breast cancer (stage I-IIIC) receiving chemotherapy, from pre- (A1) to postchemotherapy (A2) and from prechemotherapy to 6 months postchemotherapy (A3); controls were assessed at the same time-equivalent points. The primary aim assessed visual memory using the Cambridge Neuropsychological Test Automated Battery Delayed Match to Sample test by longitudinal mixed models including A1, A2, and A3 and adjusting for age, education, race, cognitive reserve score, and baseline anxiety and depressive symptoms. We also assessed trajectories of CRCI in other aspects of memory as well as in attention and executive function with computerized, paper-based, and telephone-based cognitive tests.

RESULTS

In total, 580 patients with breast cancer (mean age, 53.4 years) and 363 controls (mean age, 52.6 years) were assessed. On the Delayed Match to Sample test, the longitudinal mixed model results revealed a significant group-by-time effect ( P < .005); patients declined over time from prechemotherapy (A1) to 6 months postchemotherapy (A3; P = .005), but controls did not change ( P = .426). The group difference between patients and controls was also significant, revealing declines in patients but not controls ( P = .017). Several other models of computerized, standard, and telephone tests indicated significantly worse performance by patients compared with controls from pre- to postchemotherapy and from prechemotherapy to 6 months postchemotherapy.

CONCLUSION

This nationwide study showed CRCI in patients with breast cancer affects multiple cognitive domains for at least 6 months postchemotherapy.

Omega-3 fatty acid use for obese breast cancer patients with aromatase inhibitor-related arthralgia (SWOG S0927)

PURPOSE

Although aromatase inhibitors (AIs) prolong survival in post-menopausal breast cancer (BC) patients, AI-associated arthralgia can lead to discontinuation. Obese patients have higher rates of AI arthralgia than non-obese patients, but treatment options are limited. Omega-3 fatty acid (O3-FA) treatment for AI arthralgia has produced mixed results.

METHODS

We performed an exploratory analysis of SWOG S0927, a multicenter randomized placebo-controlled trial of O3-FA use for AI arthralgia. Post-menopausal women with stage I-III BC taking an AI were randomized to 24 weeks of O3-FAs or placebo. Brief Pain Inventory (BPI) questionnaires and fasting serum were collected at baseline, 12, and 24 weeks. The BPI assessment included worst pain, average pain, and pain interference scores (range 0-10).

RESULTS

Among the 249 participants, 139 had BMI < 30 kg/m² (56%) and 110 had BMI ≥ 30 kg/m² (44%). Among obese patients, O3-FA use was associated with significantly lower BPI worst pain scores at 24 weeks compared with placebo (4.36 vs. 5.70, p = 0.02), whereas among non-obese patients, there was no significant difference in scores between treatment arms (5.27 vs. 4.58, p = 0.28; interaction p = 0.05). Similarly, O3-FA use was associated with lower BPI average pain and pain interference scores at 24 weeks compared with placebo among obese patients, but no significant difference between treatment arms in non-obese patients (interaction p = 0.005 and p = 0.01, respectively).

CONCLUSIONS

In obese BC patients, O3-FA use was associated with significantly reduced AI arthralgia compared to placebo.

Cabozantinib versus sunitinib for previously untreated patients with advanced renal cell carcinoma (RCC) of intermediate or poor risk: Subgroup analysis of progression-free survival (PFS) and objective response rate (ORR) in the Alliance A031203 CABOSUN trial

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Background: The randomized phase 2 CABOSUN trial (NCT01835158) compared cabozantinib (C) with sunitinib (S) as initial systemic therapy in patients (pts) with RCC of intermediate or poor risk. Compared with S, C improved both PFS and ORR as assessed by independent radiology review committee (IRC). Median PFS per IRC was 8.6 mo for C vs 5.3 mo for S (HR 0.48, 95% CI 0.31-0.74 two-sided p = 0.0008), and ORR per IRC was 20% vs 9%. Methods: 157 patients were randomized 1:1 to receive C (60 mg qd) or S (50 mg qd, 4 weeks on/2 weeks off) stratified by International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk group and the presence of bone metastases. Subgroup analyses of PFS per IRC and ORR per IRC are presented based on stratification factors, age, sex, baseline ECOG status, and MET tumor expression by immunohistochemistry. The primary endpoint was investigator-assessed PFS. PFS and ORR were evaluated by IRC in a post-hoc analysis. Results: 45% of pts were ≥65 years, 78% were male, 54% were ECOG 1 or 2, 19% were poor risk, and 36% had bone metastases. MET status was determined in 131 pts; of these 47% were MET positive. The HR for PFS per IRC favored C over S across all subgroups analyzed (Table). Subgroups with poor prognostic characteristics (poor risk, ECOG 1 or 2, presence of bone metastases) had shorter median PFS for both C and S. Odds ratios for ORR also favored C over S, with the highest C ORR in the MET positive subgroup (34% C vs 10% S). Conclusions: C was associated with improved PFS and ORR compared with S in previously untreated pts with advanced RCC irrespective of baseline characteristics. Clinical trial information: NCT01835158. [Table: see text]