Abstract Venetoclax, a potent BCL‐2 inhibitor, is currently under development for treatment of t(11;14) Multiple myeloma (MM). The objective of this research was to investigate the exposure–response relationships of venetoclax for a phase 1/2 study evaluating venetoclax monotherapy or in combination with dexamethasone in relapsed or refractory MM. A total of 117 patients receiving venetoclax at 300, 600, 800, 900, or 1200 mg were included in the analysis. The impact of venetoclax exposures on efficacy (objective response rate [ORR], progression‐free survival [PFS] and overall survival [OS]) as well as safety (treatment‐emergent adverse effects (grade ≥3) of neutropenia, infection, and any grade of serious treatment‐emergent adverse effects) was evaluated. In the t(11;14)‐positive subpopulation, venetoclax exposure relationships to PFS and OS indicated a trend of longer PFS and OS with higher exposures. Moreover, logistic regression analyses for clinical response (ORR and ≥VGPR rate) demonstrated a statistically significant ( p < 0.05) relationship with exposure. Evaluation of the exposure‐safety relationships demonstrated a lack of a relationship between venetoclax exposures (AUC avg ) and grade ≥3 infections, grade ≥3 neutropenia, grade ≥3 treatment‐emergent adverse events or any grade serious treatment‐emergent adverse events. These findings support further study of venetoclax at 800 mg QD dose in combination with dexamethasone in the t(11;14)‐positive patient population where increased efficacy was observed without an increase in safety events.Clinical Trial: NCT01794520 registered 20 February 2013.
Impact of Venetoclax Exposure on Clinical Efficacy and Safety in Biomarker-Selected Patients with Relapsed or Refractory Multiple Myeloma: Implication for Dose Selection
A phase III, randomized, multicenter, open-label study of venetoclax or pomalidomide in combination with dexamethasone in patients with t(11;14)-positive relapsed/refractory multiple myeloma.
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 .