Abstract P2-08-02: Interaction of PIK3CA mutation subclasses with response to preoperative treatment with the PI3K inhibitor pictilisib in patients with estrogen receptor-positive breast cancer

Background: Although preclinical data suggest that combining PI3K inhibitors with endocrine therapy may overcome resistance, results from randomized clinical trials have failed to identify a subgroup of patients that derive a substantial benefit. This preoperative window study assessed whether adding the PI3K inhibitor pictilisib can increase the anti-tumor effects of anastrozole in primary breast cancer and aimed to identify the most appropriate patient population for combination therapy.

Methods: In this randomized, open-label, phase 2 study, 167 postmenopausal women with newly diagnosed, operable, ER-positive, HER2-negative breast cancers were recruited. Participants were randomly allocated (2:1, favoring the combination) to two-weeks of preoperative treatment with anastrozole 1 mg once daily or the combination of anastrozole 1mg with pictilisib 260 mg once daily. The primary endpoint was inhibition of tumor cell proliferation, as measured by change in Ki-67 protein expression between tumor samples taken before and at the end of treatment. Secondary endpoints include induction of apoptosis (Caspase3) and safety. Comprehensive biomarkers analyses included targeted NGS of a comprehensive cancer panel of >400 genes (Ampliseq Comprehensive Cancer panel), copy number variation analyses, and pre- and post-treatment reverse-phase protein arrays (RPPA) and RNA profiling (NanoString nCounter platform).

Results:There was significantly greater geometric mean Ki67 suppression of 82.5% (90% CI, 78.3%-85.8%) for the combination vs 70.7% (61.0%-78.0%) for anastrozole [geometric mean ratio (combination/ anastrozole) 0.60 (0.58-0.85);p=0.01]. Higher baseline Ki67, Luminal B status and/or negative PR status were associated with increased benefit from adding pictilisib. A significant interaction was observed between PIK3CA mutation subtypes [helical domain mutations (HD), kinase domain mutations (KD), wildtype (WT)] and mean Ki67 suppression; the combination/anastrozole geometric mean ratio of Ki67 suppression was 0.48 (0.27-0.84; p=0.02) for patients with HD mutations and 0.63 (0.39–1.0; p=0.05) for patients with PIK3Ca WT, compared to 1.17 (0.57–2.41; p=0.64) for patients with KD mutations. This was largely due to patients with HD mutations showing a particularly poor response to anastrozole alone [mean Ki67 suppression 53.9% (9.5%-76.5%)], that was reversed by the addition of pictilisib [mean Ki-67 suppression 78.1% (71.0%-83.4%)]. On the other hand, patients with KD mutations responded well to anastrozole alone [mean Ki-67 suppression 77.7% (57.0%-88.4%)] and showed no benefit from the addition of pictilisib [mean Ki-67 suppression 73.9% (59.8%-83.0%)]. There was no significant difference in induction of apoptosis between treatment groups. Comprehensive pre- and post-treatment biomarkers analyses will be presented.

Conclusions: Adding pictilisib to anastrozole significantly increases the anti-proliferative response to preoperative treatment with anastrozole. A significant interaction was observed between PIK3CA mutation subtypes, with patients with helical domain mutations showing a particularly poor response to anastrozole alone that was reversed by the addition of pictilisib.

Citation Format: Schmid P, Pinder S, Wheatley D, Zummit C, Macaskill EJ, Hu J, Price R, Bundred N, Hadad S, Shia A, Sarker S-J, Lim L, Mousa K, O'Brien C, Wilson TR, Lackner MR, Gendreau S, Gazinska P, Korbie D, Trau M, Mainwaring P, Thompson A, Purushotham A. Interaction of PIK3CA mutation subclasses with response to preoperative treatment with the PI3K inhibitor pictilisib in patients with estrogen receptor-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-02.

Abstract P3-10-09: Relationship between tumor infiltrating lymphocytes (TILs) and response to pembrolizumab (Pembro)+chemotherapy (Chemo) as neoadjuvant treatment (NAT) for triple-negative breast cancer (TNBC): phase Ib KEYNOTE-173 trial

Background:Increasing quantities of stromal TILs (sTILs) are associated with higher pathologic complete response (pCR) rates with conventional chemo in early-stage TNBC. We evaluated the association between sTILs and PD-L1 expression with response to pembro+chemo as NAT for TNBC in the KEYNOTE-173 trial (NCT02622074).

Methods: sTILs were quantified using light microscopy of H&E-stained slides from pretreatment and on-treatment (during first 3 weeks of pembro monotherapy) tumor biopsies by a pathologist blind to response data. Pretreatment PD-L1 expression was assessed using the PD-L1 IHC 22C3 pharmDx assay and reported as combined positive score (CPS). Endpoints were pCR rate by ypT0 ypN0 and ypT0/Tis ypN0 and objective response rate (ORR; RECIST v1.1) after the first 4 cycles of NAT (taxane±carboplatin+pembro) by MRI. sTILs and PD-L1 CPS were evaluated as continuous variables. Association between sTILs and PD-L1 CPS with response was assessed using logistic regression and area under the reciever operating curve (AUROC) analyses, with a 1-sided alpha level of 0.10. Correlation between PD-L1 and sTILs was assessed by Spearman's rank correlation coefficient. Multivariate analysis included sTILs (pretreatment and on-treatment) and PD-L1 CPS. Likelihood ratio tests were used to evaluate the added value of factors in predicting pCR rate.

Results: Of 60 total pts, 34 had tumors evaluated for pretreatment sTILs, 52 for PD-L1 CPS, and 33 for both sTILs and CPS. On-treatment sTILs were evaluated in 31 pts. Overall pCR rates were 56.7% and 60% by ypT0 ypN0 and ypT0/Tis ypN0, respectively; ORR was 78.3%. In pts evaluated for sTILs and CPS (individually), pCR rates and ORR were comparable with overall pCR rates and ORR. There was a significant correlation between pretreatment sTILs and PD-L1 CPS (ρ=0.65, P<0.001).Higher pretreatment sTILs were significantly associated with response: ypT0 ypN0 P= 0.011; ypT0/Tis ypN0 P=0.006; ORR P=0.061. On-treatment sTILs were also significantly associated with response: ypT0 ypN0 P=0.061; ypT0/Tis ypN0 P=0.041; ORR P=0.031. Pretreatment PD-L1 CPS was significantly associated with response: ypT0 ypN0 P=0.073; ypT0/is ypN0 P=0.030; and ORR P=0.021. AUROC of pretreatment sTIL association with pCR was numerically higher than with on-treatment sTILs and PD-L1 CPS (0.69 vs 0.61 vs 0.56 for ypT0ypN0 and 0.72 vs 0.67 vs 0.62 for ypT0/Tis ypN0). Responders had higher median pretreatment sTIL levels vs nonresponders: 45% [10, 75] vs 10% [5, 20] for pCR rate by ypT0 ypN0 and 52.5% [10, 73.8] vs 10% [5, 20] for pCR rate by ypT0/Tis ypN0; 25% [5, 70] vs 10% [6.3, 27.5] for ORR. In multivariate analysis, only pretreatment sTILs were significant for both pCR endpoints (ypT0 ypN0 P=0.031; ypT0/Tis ypN0 P=0.034). Likelihood ratio tests demonstrated that for both pCR endpoints, PD-L1 CPS (P=0.683/P=0.422) and on-treatment sTILs (P=0.984/P=0.568) did not add significantly more value to pretreatment sTILs when predicting pCR.

Conclusions:Higher quantities of pretreatment sTILs and PD-L1 CPS and on-treatment sTILs were significantly associated with higher pCR rates and ORR in primary TNBC treated with pembro and NAT.

Citation Format: Loi S, Schmid P, Cortés J, Park YH, Muñoz-Couselo E, Kim S-B, Sohn J, Im S-A, Holgado E, Foukakis T, Kuemmel S, Dent R, Wang A, Aktan G, Karantza V, Salgado R. Relationship between tumor infiltrating lymphocytes (TILs) and response to pembrolizumab (Pembro)+chemotherapy (Chemo) as neoadjuvant treatment (NAT) for triple-negative breast cancer (TNBC): phase Ib KEYNOTE-173 trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-10-09.

Abstract P6-21-01: Xentuzumab (BI 836845), an insulin-like growth factor (IGF)-neutralizing antibody (Ab), combined with exemestane and everolimus in hormone receptor-positive (HR+) locally advanced/metastatic breast cancer (LA/mBC): Randomized phase 2 results

Background:

Xentuzumab (Xen), an IGF-1/-2-neutralizing Ab, binds IGF-1 and IGF-2, inhibits their growth-promoting signaling, and suppresses AKT activation by everolimus (Ev). This Phase 1b/2 trial evaluates Xen in combination with Ev and exemestane (Ex) in HR+/HER2− LA/mBC.

Methods:

The two-arm, open-label, randomized Phase 2 part enrolled female patients (pts) with HR+/HER2− LA/mBC not amenable to curative therapy and refractory to nonsteroidal aromatase inhibitors. Pts were randomized (1:1) to: oral Ev (10 mg/d) + Ex (25 mg/d); or Xen (1000 mg/wk iv) + Ev (10 mg/d) + Ex (25 mg/d). Randomization was stratified by visceral metastases (VM; Y vs N). Treatment continued in 28-day cycles until progression, intolerable adverse events (AEs) or other reasons for discontinuation. Primary endpoint was progression-free survival (PFS), with an interim futility analysis incorporated in the study design.

Results:

Following the results of the interim analysis, the Data Monitoring Committee (DMC) advised early termination of the trial and discontinuation of Xen treatment. Thus, Xen treatment exposure time and time-to-event data for the Xen+Ev+Ex arm are limited. Of the 139 women treated (Xen+Ev+Ex 70; Ev+Ex 69), 77% had VM. Median PFS was not significantly different between arms (Xen+Ev+Ex vs Ev+Ex, 7.3 vs 5.6 months; HR [95% CI] 0.97 [0.57–1.65]; p=0.91). In a pre-specified subgroup of pts without VM, Xen+Ev+Ex showed favorable PFS vs Ev+Ex (HR 0.21 [0.05–0.98]; Pint=0.0141). Pint values <0.05 were also observed for ad hoc subgroups: measurable disease at baseline; bone-only metastases. Rates of total AEs/grade ≥3 AEs/drug-related AEs were similar between arms (Xen+Ev+Ex, 100/60/96%; Ev+Ex, 99/58/96%). The most common AEs overall were diarrhea (44 vs 33%), mucosal inflammation (39 vs 32%), rash (34 vs 33%) and stomatitis (34 vs 38%); most were grade 1/2. 6% of pts in the Xen+Ev+Ex arm discontinued Xen due to AEs. Ev/Ex discontinuations (Xen+Ev+Ex vs Ev+Ex) occurred in 13/6% vs 23/6%; 1 pt each in the Xen+Ev+Ex arm died from pneumonitis and liver injury and 1 pt each in the Ev+Ex arm died from Burkitt's lymphoma, acute kidney injury and metastases to the peritoneum.

Conclusion:

In the overall population, PFS did not improve with the addition of Xen to Ev+Ex and the trial was therefore discontinued early. Nevertheless, a favorable signal was observed in the pre-specified subgroup of pts without VM when treated with Xen+Ev+Ex, which warrants additional investigation. The safety profile was comparable between arms.

Citation Format: Crown J, Sablin M-P, Cortés J, Bergh J, Im S-A, Lu Y-S, Martínez N, Neven P, Lee KS, Morales S, Pérez-Fidalgo JA, Adamson D, Goncalves A, Prat A, Jerusalem G, Schlieker L, Espadero R-M, Bogenrieder T, Chin-Lun Huang D, Schmid P. Xentuzumab (BI 836845), an insulin-like growth factor (IGF)-neutralizing antibody (Ab), combined with exemestane and everolimus in hormone receptor-positive (HR+) locally advanced/metastatic breast cancer (LA/mBC): Randomized phase 2 results [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-21-01.

Abstract OT2-06-04: MORPHEUS: A phase Ib/II trial platform evaluating the safety and efficacy of multiple cancer immunotherapy combinations in patients with hormone receptor–positive and triple-negative breast cancer

Background:

Cancer immunotherapy (CIT) has significantly improved overall survival across multiple tumor types, but only subsets of patients experience durable response with single-agent CIT. Combinations of CIT with targeted therapy or chemotherapy may be needed in order to target multiple cancer immune escape mechanisms simultaneously, thus providing personalized treatment options that extend clinical benefit to more patients. The MORPHEUS platform includes multiple phase Ib/II trials designed to identify early signals of safety and activity of CIT combinations. Using a randomized trial design, multiple CIT combination arms are compared with a single standard-of-care control arm. These trials have the flexibility to open new treatment arms with novel CIT combinations as they become available and to close arms that show minimal activity or unacceptable toxicity. Here we describe MORPHEUS trials in patients with metastatic or unresectable locally advanced hormone receptor–positive (HR+BC) or triple-negative breast cancer (TNBC), 2 patient populations in need of more treatment options.

Trial design:

MORPHEUS-HR+BC (NCT03280563) will enroll patients with metastatic or unresectable locally advanced HR+BC who have progressed during or after first-line treatment with a cyclin-dependent kinase (CDK) 4/6 inhibitor and whose tumors do not express human epidermal growth factor 2 (HER2). MORPHEUS-TNBC (NCT03424005) will enroll patients with metastatic or unresectable locally advanced TNBC who have progressed during or after first-line treatment with chemotherapy. For both studies, key inclusion criteria include Eastern Cooperative Oncology Group performance status of 0-1 (stage 1) or 0-2 (stage 2) and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Key exclusion criteria include prior treatment with T-cell co-stimulating or immune checkpoint blockade therapies, and symptomatic, untreated, or actively progressing central nervous system metastases. Patients in both trials will be randomized to one of the CIT atezolizumab combination arms or a control arm (up to 5 arms in HR+BC and up to 6 arms in TNBC). Patients experiencing loss of clinical benefit or unacceptable toxicity in stage 1 may be eligible to switch to a different CIT atezolizumab combination arm in stage 2. Primary endpoints are safety measures and investigator-assessed objective response rate per RECIST v1.1. Progression-free survival, overall survival, duration of response, clinical benefit rate (HR+BC) or disease control rate (TNBC) are among the secondary endpoints. Exploratory biomarkers will also be examined.

Citation Format: Yardley DA, Abu-Khalaf M, Boni V, Brufsky A, Emens LA, Gutierrez M, Hurvitz S, Im S-A, Loi S, McCune SL, Schmid P, O'Hear C, Zhang X, Vidal GA. MORPHEUS: A phase Ib/II trial platform evaluating the safety and efficacy of multiple cancer immunotherapy combinations in patients with hormone receptor–positive and triple-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-06-04.

Abstract OT3-04-03: KEYNOTE-756: A randomized, double-blind, phase III study of pembrolizumab versus placebo in combination with neoadjuvant chemotherapy and adjuvant endocrine therapy for high-risk early-stage ER+/HER2– breast cancer

Background:Although ER+/HER2– breast cancer has a better overall prognosis than other breast cancer subtypes, there is a high-risk subpopulation characterized by high-grade tumors and decreased sensitivity to endocrine therapy, higher responsiveness to chemotherapy and worse prognosis. A large meta-analysis of prospective studies focusing on neoadjuvant chemotherapy (NAC) for treatment of stage I-III breast cancer demonstrated that increased pathologic complete response (pCR) rates at surgery were associated with improved survival. This correlation was observed across triple-negative breast cancer (TNBC), HER2+ breast cancer, and high-grade HR+/HER2- breast cancer. Specifically, patients with a pCR after NAC had a 5-year event-free survival (EFS) rate of 90%, whereas patients who did not achieve a pCR had a 5-year EFS rate of 60%.Therefore, increasing pCR rates after NAC may have a substantial impact for patients with high-risk early-stage HR+/HER2– breast cancer. KEYNOTE-756 is a global, randomized, double-blind, phase III study of pembrolizumab (vs placebo) + chemotherapy as neoadjuvant treatment, followed by pembrolizumab (vs placebo) plus endocrine therapy as adjuvant treatment for patients with high-risk, early-stage ER+/HER2– breast cancer.

Methods: Patients with T1c-2 cN1-2 or T3-4 cN0-2 grade 3 or grade 2 with Ki-67 ≥30%, invasive, ductal ER+/HER2– breast cancerwill be stratified by lymph node involvement (positive vs negative), tumor PD-L1 status (positive vs negative), ER positivity (≥10% vs <10%), and anthracycline dosing schedule (Q3W vs Q2W), and then randomized 1:1 to receive neoadjuvant treatment with pembrolizumab 200 mg Q3W or placebo in combination with paclitaxel (80 mg/m2 QW) for 4 cycles followed by (doxorubicin [60 mg/m2] or epirubicin [100 mg/m2]) plus cyclophosphamide (600 mg/m2) Q2/3W for another 4 cycles. After definitive surgery (± radiation therapy, as indicated), patients will receive adjuvant treatment with pembrolizumab (200 mg Q3W) or placebo for 9 additional administrations, in combination with endocrine therapy, which can be given for up to 10 years. Co-primary end points are pCR rate and EFS. Secondary end points are safety and overall survival. The global study will open in North America and Latin America, Europe, and Asia Pacific in the second half of 2018.

Citation Format: Cardoso F, Bardia A, Andre F, Cescon DW, McArthur H, Telli M, Loi S, Cortés J, Schmid P, Harbeck N, Denkert C, Jackisch C, Jia L, Tryfonidis K, Karantza V. KEYNOTE-756: A randomized, double-blind, phase III study of pembrolizumab versus placebo in combination with neoadjuvant chemotherapy and adjuvant endocrine therapy for high-risk early-stage ER+/HER2– breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-04-03.

Systematic review of the impact of breast-conserving surgery on cancer outcomes of multiple ipsilateral breast cancers

Background

The clinical effectiveness of treating ipsilateral multifocal (MF) and multicentric (MC) breast cancers using breast‐conserving surgery (BCS) compared with the standard of mastectomy is uncertain. Inconsistencies relate to definitions, incidence, staging and intertumoral heterogeneity. The primary aim of this systematic review was to compare clinical outcomes after BCS versus mastectomy for MF and MC cancers, collectively defined as multiple ipsilateral breast cancers (MIBC).

Methods

Comprehensive electronic searches were undertaken to identify complete papers published in English between May 1988 and July 2015, primarily comparing clinical outcomes of BCS and mastectomy for MIBC. All study designs were included, and studies were appraised critically using the Newcastle–Ottawa Scale. The characteristics and results of identified studies were summarized.

Results

Twenty‐four retrospective studies were included in the review: 17 comparative studies and seven case series. They included 3537 women with MIBC undergoing BCS; breast cancers were defined as MF in 2677 women, MC in 292, and reported as MIBC in 568. Six studies evaluated MIBC treated by BCS or mastectomy, with locoregional recurrence (LRR) rates of 2–23 per cent after BCS at median follow‐up of 59·5 (i.q.r. 56–81) months. BCS and mastectomy showed apparently equivalent rates of LRR (risk ratio 0·94, 95 per cent c.i. 0·65 to 1·36). Thirteen studies compared BCS in women with MIBC versus those with unifocal cancers, reporting LRR rates of 2–40 per cent after BCS at a median follow‐up of 64 (i.q.r. 57–73) months. One high‐quality study reported 10‐year actuarial LRR rates of 5·5 per cent for BCS in 300 women versus 6·5 per cent for mastectomy among 887 women.

Conclusion

The available studies were mainly of moderate quality, historical and underpowered, with limited follow‐up and biased case selection favouring BCS rather than mastectomy for low‐risk patients. The evidence was inconclusive, weakening support for the St Gallen consensus and supporting a future randomized trial.

Abstract P6-12-14: Quality of life and ability to work in patients at different disease stages of HER2+ breast cancer

OBJECTIVES: Health-related quality of life (HRQoL) and ability to work in patients treated for HER2+ early breast cancer (EBC) are poorly understood. This study compared HRQoL and ability to work in 3 HER2+ patient cohorts: EBC during adjuvant treatment, EBC after treatment, and metastatic disease (MBC).

METHODS: A cross-sectional observational cohort study of 299 female consenting patients with HER2+BC, from 14 UK secondary care centres. Group1 (n=89): receiving targeted HER2 therapy±chemotherapy for EBC; Group2 (n=108): in follow up post-targeted treatment for eBC; Group3 (n=102): MBC on treatment. Data collected between Dec 2016-Mar 2017: HRQoL, demographic and employment status data collected via patient-reported questionnaires (including EQ-5D-5L and Functional Assessment of Cancer Therapy [FACT-B]); clinical data collected from medical records. Inter-group differences were assessed using univariate Analysis of variance (ANOVA) and chi-square tests as appropriate. [NCT03099200].

RESULTS: Table1 shows patient demographics, disease characteristics, employment status, and EQ-5D-5L scores. Group1 and Group2 patients did not differ in overall health utility or visual analogue scale (VAS) scores. However, Group3 patients reported significantly poorer health utility than Group1 (p<0.02) and Group2 (p<0.001), and significantly worse VAS scores than Group2 (p<0.001). Significantly fewer Group2 patients and more Group3 patients were unable to work (p<0.003), and fewer Group3 patients were employed than expected (by chi-square, p<0.003).

CONCLUSIONS: HRQoL in patients with EBC was similar whether on or off treatment, and better than those with MBC. HRQoL scores reported on the generic EQ-5D will be compared with those from the disease-specific FACT-B. A smaller proportion of patients with MBC were employed compared to the EBC groups, reflecting the impact of advanced disease. Fewer patients with EBC reported being unable to work than we expected, suggesting these patients maintain function.

Table1

 Group1 (n=89)Group2 (n=108)Group3 (n=102)Age (years)↑55 (11)58 (11)55 (11)Hormone receptor status¥Positive64 (72%)84 (78%)74 (73%)Negative25 (28%)24 (22%)26 (26%)Unknown0 (0%)0 (0%)2 (2%)Time since diagnosis (months)+EBC9 (6)45 (32) (n=103)80 (82) (n=71*)MBC--39 (36) (n=101)Employment status¥Employed45 (51%)55 (51%)28 (28%)§Not employed41 (46%)52 (48%)69 (68%)Retired22 (25%)39 (36%)33 (32%)Unable to work7 (8%)5 (5%)§27 (27%)§Other12 (14%)8 (7%)9 (9%)Unknown3 (3%)1 (1%)5 (5%)EQ-5D summary scoresVisual analogue scale72.7 (18.4)†77.0 (17.5)†65.8 (22.9)† (n=99)Utility value0.809 (0.170)† (n=86)0.818 (0.181)†0.695 (0.262)† (n=97)↑mean (standard deviation); ¥n (%); +median (interquartile range); *excludes 27/102 patients (27%) with de novo MBC. Bold text: observed differences between three groups at significance thresholds of ‡p<0.05, §p<0.003 or †p<0.001. EBC/MBC: early/metastatic breast cancer. %s have been rounded so may not total 100%

Citation Format: Verrill M, Wardley A, Retzler J, Smith AB, McNicol D, Dando S, Tran I, Leslie I, Schmid P. Quality of life and ability to work in patients at different disease stages of HER2+ breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-14.

Abstract PD6-12: Withdrawn

This abstract was withdrawn by the authors.

Abstract OT1-03-01: Chemotherapy-free trastuzumab and pertuzumab in HER2 [+] breast cancer: FDG-PET response-adapted strategy. The PHERGain study

BACKGROUND:

Several studies have confirmed that a significant subset of patients (pts) with early stage HER2[+]breast cancer (BC) achieve pathological complete response (pCR) with a dual HER2 neoadjuvant blockade without chemotherapy (chemo). Early metabolic evaluation using 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) might help to recognize those pts with a higher likelihood of obtaining a pCR and an excellent outcome with a chemo-free strategy.

TRIAL DESIGN:

This is a randomized, multicenter, non-comparative phase II trial. Pts age ≥ 18 years with centrally-confirmed, treatment-naïve, HER2 [+] operable BC will be randomized, in a 1:4 ratio, and stratified by HR status, to receive docetaxel, carboplatin, trastuzumab, and pertuzumab (TCHP) (cohort A), or trastuzumab and pertuzumab (HP) ± endocrine therapy (ET) according to HR status (cohort B). Centrally-reviewed 18F-FDG PET/CT scans will be performed prior to randomization and after 2 cycles of therapy. Pts allocated into cohort A will continue with the same therapy for a total of 6 cycles regardless of 18F-FDG PET/CT results. Pts enrolled into cohort B showing at least a 40% reduction of the SUVmax on 18F-FDG PET/CT respect to baseline (PET responders) will continue with the same therapy for a total of 8 cycles. PET non-responders pts will receive 6 cycles of TCHP. After surgery, cohort B/PET responders pts who do not achieve a pCR will receive 6 cycles of TCHP. Moreover, all pts from cohorts A/B must complete 18 cycles of HP, along with adjuvant ET and radiotherapy (RT) according to HR status and institutional practices, respectively. Pts with subclinic metastases will be assigned to cohort C to receive 6 cycles of TCHP. Surgery and RT will be evaluated on a case-by-case basis on cohort C, and all pts will continue with HP for at least 12 additional cycles ± ET according to HR status.

The first co-primary endpoint is to evaluate the rate of pCR defined as the absence of invasive disease in the breast and axilla (ypT0/isN0) achieved with HP ± ET in PET responders pts (cohort B/PET responders).The second co-primary endpoint is to evaluate 3-year (3-y) invasive disease-free survival (iDFS) rate defined as time from the first date of no disease to invasive recurrence, new invasive disease, or death by any cause in cohort B.

Total accrual will be 400 pts. Considering a 10% and 25% of drop-out rates at the time of first and second co-primary analysis, the study will be positive if ≥41 pts achieved a pCR in cohort B/PET responders; or if we observe ≤14 events of 3-y iDFS in cohort B. Decisions will be based on one-sided, exact binomial test. With a 2.5% type I error rate (H0: pCR ≤20% and 3-y iDFS ≤89%) and 80% power (HA: pCR ≥30% and 3-y iDFS ≥95%).

The secondary objectives are to evaluate other definitions of pCR, rates of breast-conserving surgery, tumor response by magnetic resonance imaging, optimal 18F-FDG PET cut-off for pCR and other 18F-FDG PET quantification parameters for pCR prediction, DFS, distant-DFS, overall survival, progression-free survival, and health-related quality of life. Translational sub-studies will analyze biomarkers that may be predictive of response to dual HER2 blockade with HP.

Citation Format: Llombart-Cussac A, Curigliano G, Gebhart G, Gligorov J, Khaldoun K, Marmé F, Prat A, Schmid P, Cortes J, Perez J. Chemotherapy-free trastuzumab and pertuzumab in HER2 [+] breast cancer: FDG-PET response-adapted strategy. The PHERGain study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-03-01.

Long-term effectiveness of recommended boosted protease inhibitor-based antiretroviral therapy in Europe

OBJECTIVES

The aim of the study was to evaluate the long-term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)-, darunavir/ritonavir (DRV/r)-, and lopinavir/ritonavir (LPV/r)-containing regimens.

METHODS

Data were analysed for 5678 EuroSIDA-enrolled patients starting a DRV/r-, ATZ/r- or LPV/r-containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART-naïve subjects (8%) at ritonavir-boosted protease inhibitor (PI/r) initiation; (2) ART-experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV-1 RNA copies/mL; and (3) ART-experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan-Meier and multivariable Cox models were used to compare risks of failure by PI/r-based regimen. The main analysis was performed with intention-to-treat (ITT) ignoring treatment switches.

RESULTS

The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log-rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART-naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment-experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r-based ART.

CONCLUSIONS

Although confounding by indication and calendar year cannot be completely ruled out, in ART-experienced subjects the long-term effectiveness of DRV/r-containing regimens appears to be greater than that of ATZ/r and LPV/r.

Significant Changes in Circulating Plasma Levels of IGF1 and IGFBP3 after Conventional or Dose-Intensified Adjuvant Treatment of Breast Cancer Patients with one to three Positive Lymph Nodes

The insulin-like growth factor 1 (IGF1) and its binding protein IGFBP3 (insulin-like growth factor binding protein 3) play a pivotal role during the growth and development of tissues. The purpose of this study was to evaluate the influence of anthracycline- and taxane-containing adjuvant chemotherapy in breast cancer patients on the circulating plasma levels of IGF1 and its main binding protein, IGFBP3. This investigation was part of a prospective randomized phase III study in which breast cancer patients were treated with either conventional or dose-intensified adjuvant chemotherapy. The factors were quantified in the plasma of 151 patients with a commercially available sandwich enzyme immunoassay. Before therapy, both parameters were within the normal range in most patients (n=145 and n=144). After therapy, both factors had increased significantly by 29% (IGF1) and 19% (IGFBP3), with the highest increase being observed in the dose-intensified group. Correlations with patient and tumor characteristics revealed a relatively higher increase in both parameters in premenopausal patients, patients with lower-grade tumors, more positive lymph nodes, larger tumor volume, and positive hormone receptor status. No correlation was found with the HER2 expression of the tumors.

Downregulation von LH bei der Hündin nach Anwendung des GnRH-Agonisten Buserelin in Implantatform

Gegenstand und Ziel: Darstellung der Downregulation von LH bei der Hündin nach Anwendung eines Slow-Release-GnRH-Implantats mit dem Wirkstoff Buserelin. Material und Methoden: Zur Ausschaltung negativ rückkoppelnder Wirkungen endogener Sexualhormone wurden neun Hündinnen ovariohysterektomiert. Zur Anwendung kam der Wirkstoff Buserelinacetat in Form des Slow-Release-Implantats Profact Depot®, wobei jeweils drei Hündinnen Implantate mit 3,3 mg, 6,6 mg oder 13,2 mg subkutan appliziert wurden. Die Charakterisierung der Verfügbarkeit von LH erfolgte durch punktuelle sowie durch sequenzielle Blutentnahmen über 6-stündige Zeitfenster. Folgende Parameter wurden erfasst: AUC (Area Under the Curve), Basalkonzentration, Anzahl der Pulse und maximale Pulsamplitude. Ergebnisse: Dosisabhängigkeiten waren nicht feststellbar, was darauf hindeutet, dass die niedrigste Dosis bereits maximal wirksam war. Für die weitere Auswertung wurden die Tiere daher zu einer Gruppe zusammengefasst. Ein zunehmend stärker werdender Effekt der Downregulation zeigte sich von der 2. bis zur 26. Woche nach der Implantation, die Wirkdauer lag bei ca. 34 Wochen. Eine Stunde nach der Implantation kam es zu einem signifikanten Anstieg auf fast das Doppelte des Ausgangswerts. Danach blieb das LH-Niveau über weitere 8 Stunden erhöht. Schlussfolgerung: Wie beim Rüden führt Buserelin auch bei der Hündin zu einer Downregulation der LH-Sekretion, der eine initiale, über mehrere Stunden anhaltende erhöhte LH-Freisetzung vorausgeht. Diese muss im Zusammenhang mit den unerwünschten Wirkungen gesehen werden, die bei der Downregulation der Ovarfunktion der Hündin mittels Slow-Release-GnRH-Analoga auftreten. Klinische Relevanz: Die Unterbindung des initialen Anstiegs der LH-Konzentration ist Voraussetzung für eine erfolgreiche Anwendung von Slow-Release-GnRH-Analoga zur Downregulation der Sexualfunktion der Hündin.

On the potential of a short-term intensive intervention to interrupt HCV transmission in HIV-positive men who have sex with men: A mathematical modelling study

Increasing access to direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV) infection and decelerating the rise in high-risk behaviour over the next decade could curb the HCV epidemic among HIV-positive men who have sex with men (MSM). We investigated if similar outcomes would be achieved by short-term intensive interventions like the Swiss-HCVree-trial. We used a HCV transmission model emulating two 12-months intensive interventions combining risk counselling with (i) universal DAA treatment (pangenotypic intervention) and (ii) DAA treatment for HCV genotypes 1 and 4 (replicating the Swiss-HCVree-trial). To capture potential changes outside intensive interventions, we varied time from HCV infection to treatment in clinical routine and overall high-risk behaviour among HIV-positive MSM. Simulated prevalence dropped from 5.5% in 2016 to ≤2.0% over the intervention period (June/2016-May/2017) with the pangenotypic intervention, and to ≤3.6% with the Swiss-HCVree-trial. Assuming time to treatment in clinical routine reflected reimbursement restrictions (METAVIR ≥F2, 16.9 years) and stable high-risk behaviour in the overall MSM population, prevalence in 2025 reached 13.1% without intensive intervention, 11.1% with the pangenotypic intervention and 11.8% with the Swiss-HCVree-trial. If time to treatment in clinical routine was 2 years, prevalence in 2025 declined to 4.8% without intensive intervention, to 2.8% with the pangenotypic intervention, and to 3.5% with the Swiss-HCVree-trial. In this scenario, the pangenotypic intervention and the Swiss-HCVree-trial reduced cumulative (2016-2025) treatment episodes by 36% and 24%, respectively. Therefore, intensive interventions could reduce future HCV treatment costs and boost the benefits of long-term efforts to prevent high-risk behaviour and to reduce treatment delay. But if after intensive interventions treatment is deferred until F2, short-term benefits of intensive interventions would dissipate in the long term.

Unprecedented sensitivity of the planar yeast estrogen screen by using a spray-on technology

The planar yeast estrogen screen (p-YES) can serve as a highly valuable and sensitive screening tool for the detection of estrogenic compounds in various sample matrices such as water and wastewater, personal care products and foodstuff. The method combines the separation of sample constituents by thin layer chromatography with the direct detection of estrogenic compounds on the surface of the HPTLC-plate. The previous protocol using the immersion of a normal phase silica HPTLC-plate in a cell suspension for bio-autography resulted in blurred signals due to the accelerated diffusion of compounds on the wet surface of the HPTLC-plate. Here, the application of the yeast cells by spraying on the surface of the HPTLC-plate is described as an alternative approach. The presented method for the hyphenation of normal phase thin layer chromatography with a yeast estrogen screen results in much sharper signals compared to reports in previous publications. Satisfying results were achieved using cultures with cell densities of 1000 FAU. Due to the reduced signal broadening, lower limits of quantification for estrogenic compounds were achieved (Estrone (E1)=2pg/zone, 17β-estradiol (E2)=0.5pg/zone, 17α-ethinylestradiol (EE2)=0.5pg/zone and Estriol (E3)=20pg/zone). As demonstrated, it is possible to characterize profiles of estrogenic activity of wastewater samples with high quality and reproducibility. The improved sensitivity opens the stage for applications using native samples from waste- or even surface water directly applied on HPTLC-plates without the need for prior sample treatment by e.g. solid phase extraction.

Incidence of cancer and overall risk of mortality in individuals treated with raltegravir-based and non-raltegravir-based combination antiretroviral therapy regimens

Objectives

There are currently few data on the long‐term risk of cancer and death in individuals taking raltegravir (RAL). The aim of this analysis was to evaluate whether there is evidence for an association.

Methods

The EuroSIDA cohort was divided into three groups: those starting RAL‐based combination antiretroviral therapy (cART) on or after 21 December 2007 (RAL); a historical cohort (HIST) of individuals adding a new antiretroviral (ARV) drug (not RAL) to their cART between 1 January 2005 and 20 December 2007, and a concurrent cohort (CONC) of individuals adding a new ARV drug (not RAL) to their cART on or after 21 December 2007. Baseline characteristics were compared using logistic regression. The incidences of newly diagnosed malignancies and death were compared using Poisson regression.

Results

The RAL cohort included 1470 individuals [with 4058 person‐years of follow‐up (PYFU)] compared with 3787 (4472 PYFU) and 4467 (10 691 PYFU) in the HIST and CONC cohorts, respectively. The prevalence of non‐AIDS‐related malignancies prior to baseline tended to be higher in the RAL cohort vs. the HIST cohort [adjusted odds ratio (aOR) 1.31; 95% confidence interval (CI) 0.95–1.80] and vs. the CONC cohort (aOR 1.89; 95% CI 1.37–2.61). In intention‐to‐treat (ITT) analysis (events: RAL, 50; HIST, 45; CONC, 127), the incidence of all new malignancies was 1.11 (95% CI 0.84–1.46) per 100 PYFU in the RAL cohort vs. 1.20 (95% CI 0.90–1.61) and 0.83 (95% CI 0.70–0.99) in the HIST and CONC cohorts, respectively. After adjustment, there was no evidence for a difference in the risk of malignancies [adjusted rate ratio (RR) 0.73; 95% CI 0.47–1.14 for RALvs. HIST; RR 0.95; 95% CI 0.65–1.39 for RALvs. CONC] or mortality (adjusted RR 0.87; 95% CI 0.53–1.43 for RALvs. HIST; RR 1.14; 95% CI 0.76–1.72 for RALvs. CONC).

Conclusions

We found no evidence for an oncogenic risk or poorer survival associated with using RAL compared with control groups.