Yu, Yao

AbstractVenetoclax (Ven) is a selective small‐molecule inhibitor of BCL‐2 that exhibits antitumoral activity against MM cells with t(11;14) translocation. We evaluated the safety and efficacy of Ven and dexamethasone (VenDex) combination in patients with t(11;14) positive relapsed/refractory (R/R) multiple myeloma (MM). This open‐label, multicenter study had two distinct phases (phase one [P1], phase two [P2]). Patients in both phases received VenDex (oral Ven 800 mg/day + oral Dex 40 mg [20 mg for patients ≥75 years] on days 1, 8, and 15, per 21–day cycle). The primary objective of the P1 VenDex cohort was to assess safety and pharmacokinetics. Phase two further evaluated efficacy with objective response rate (ORR) and very good partial response or better. Correlative studies explored baseline BCL2 (BCL‐2) and BCL2L1 (BCL‐XL) gene expression, cytogenetics, and recurrent somatic mutations in MM. Twenty and 31 patients in P1 and P2 with t(11;14) positive translocation received VenDex. P1/P2 patients had received a median of 3/5 lines of prior therapy, and 20%/87% were refractory to daratumumab. Predominant grade 3/4 hematological adverse events (AEs) with ≥10% occurrence included lymphopenia (20%/19%), neutropenia (15%/7%), thrombocytopenia (10%/10%), and anemia (5%/16%). At a median follow‐up of 12.3/9.2 months, ORR was 60%/48%. The duration of response estimate at 12 months was 50%/61%, and the median time to progression was 12.4/10.8 months. In biomarker evaluable patients, response to VenDex was independent of concurrent del(17p) or gain(1q) and mutations in key oncogenic signaling pathways, including MAPK and NF‐kB. VenDex demonstrated efficacy and manageable safety in heavily‐pre‐treated patients with t(11;14) R/R MM.

Purpose The known epithelial ovarian cancer (EOC) susceptibility genes account for less than 50% of the heritable risk of ovarian cancer suggesting that other susceptibility genes exist. The aim of this study was to evaluate the contribution to ovarian cancer susceptibility of rare deleterious germline variants in a set of candidate genes. Methods We sequenced the coding region of 54 candidate genes in 6385 invasive EOC cases and 6115 controls of broad European ancestry. Genes with an increased frequency of putative deleterious variants in cases versus controls were further examined in an independent set of 14 135 EOC cases and 28 655 controls from the Ovarian Cancer Association Consortium and the UK Biobank. For each gene, we estimated the EOC risks and evaluated associations between germline variant status and clinical characteristics. Results The ORs associated for high-grade serous ovarian cancer were 3.01 for PALB2 (95% CI 1.59 to 5.68; p=0.00068), 1.99 for POLK (95% CI 1.15 to 3.43; p=0.014) and 4.07 for SLX4 (95% CI 1.34 to 12.4; p=0.013). Deleterious mutations in FBXO10 were associated with a reduced risk of disease (OR 0.27, 95% CI 0.07 to 1.00, p=0.049). However, based on the Bayes false discovery probability, only the association for PALB2 in high-grade serous ovarian cancer is likely to represent a true positive. Conclusions We have found strong evidence that carriers of PALB2 deleterious mutations are at increased risk of high-grade serous ovarian cancer. Whether the magnitude of risk is sufficiently high to warrant the inclusion of PALB2 in cancer gene panels for ovarian cancer risk testing is unclear; much larger sample sizes will be needed to provide sufficiently precise estimates for clinical counselling.

TPS8554 Background: BCL-2 is an anti-apoptotic protein important for myeloma cell survival. Venetoclax (Ven) is a highly selective, potent, oral BCL-2 inhibitor, that has shown promise in clinical studies as monotherapy or in combination with other agents in patients with t(11;14)-positive relapsed/refractory multiple myeloma (RRMM; Kumar et al. Blood. 2017; Costa et al. ASH 2018. Abstr. #303; Harrison et al. ASH 2019. Abstr. #142; Bahlis et al. ASH 2019. Abstr. #925; Kaufman et al. ASH 2019. Abstr. #926). Notably, t(11;14)-positive MM is more dependent on BCL-2 for cell survival, which, together with these clinical data, suggests that Ven combined with dexamethasone (Dex) may provide greater clinical benefit versus standard therapies, like pomalidomide (Pom), in this biomarker-defined patient population. This ongoing Phase 3 study (CANOVA; NCT03539744) aims to evaluate the safety and efficacy of VenDex vs PomDex in t(11;14)-positive RRMM. Methods: Eligible patients (≥18 years) must have t(11;14)-positive RRMM per central lab, an ECOG performance status ≤2, received ≥2 prior lines of therapy, previously received a proteasome inhibitor, and must be refractory to lenalidomide and last line of therapy. Patients cannot have history of treatment with Ven, Pom, or other BCL-2 inhibitors. Patients will be randomized 1:1 to Ven (800 mg orally, once-daily) or Pom (4 mg orally, once-daily on days 1-21 of 28-day cycles). Patients in both groups will receive 40 mg Dex (20 mg for patients ≥75 years) once weekly. Treatment will continue until disease progression, unacceptable toxicity, or withdrawal from study. Patients will be stratified based on age at randomization ( < 65 vs ≥65 years), prior lines of therapy (2 to 3 vs ≥4), and International Staging System stage at screening (I vs II vs III). The primary endpoint is progression-free survival (PFS) per independent review committee (IRC) assessment based on International Myeloma Working Group criteria. The final PFS analysis will be performed when approximately 147 PFS events per IRC are observed. Secondary endpoints are response rate, patient-reported outcomes, overall survival, duration of response, times to response and progression, minimal residual disease negativity rate, safety, and Ven pharmacokinetics. Approximately 244 patients will be enrolled; as of January 21, 2020, 28 patients have been randomized (from 19 sites in 12 countries) and enrollment is ongoing. Clinical trial information: NCT03539744 .