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

582

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]