Background: The objective of this work was to evaluate the relationship between the response rates and median overall survival (OS) in higher-risk myelodysplastic syndrome (HR-MDS) to determine whether response rates could be used as predictors of median OS. Methods: Relevant MDS clinical trials were identified through a review of published literature. Weighted linear regression was performed with various linearizing transformations of response rates and median OS using the in-house built HR-MDS clinical trials database. Covariates of interest were evaluated using a forward inclusion, backward elimination covariate model building procedure at α=0.01 and α=0.005, respectively. Results: Twenty-five trials involving 38 cohorts were included in the meta-analysis. The analysis demonstrated that partial response (PR) or better rate (sum of complete response (CR), marrow complete response (mCR) and PR rates) was a strong predictor of median OS (adjusted R2=0.64). The median OS was 3.3 months longer (P < 0.005) with azacitidine treatment compared to treatment with other drugs for a given response rate and prior therapy status. We also have shown that the median OS of treatment naïve HR-MDS patients was 4.5 months longer (P < 0.0001) compared to that of previously treated patients for a given response rate and treatment group. Conclusion: Significant correlation between PR or better rate and median OS in HR-MDS highlights the potential to use PR or better rate as a surrogate endpoint to accelerate development of novel therapies for MDS.

Background: Response rates such as overall response rate (ORR), complete response (CR) and complete response with incomplete blood recovery (CRi) can be evaluated in a much shorter period of time than overall survival (OS), potentially accelerating decision making during drug development. The objective of this work was to evaluate the relationship between ORR, CR, CRi or better (CRi+CR) rates and median OS to determine whether response rates could be used as predictors of median OS in acute myeloid leukemia (AML). Methods: A review of published literature was conducted to identify relevant AML clinical trials. Weighted linear regression was performed with various linearizing transformations of response rates and median OS. Covariates of interest were evaluated using a forward inclusion, backward elimination covariate model building procedure at α=0.01 and α=0.005, respectively. Results: Twenty trials involving 26 cohorts were included in the meta-analysis. Azactidine treatment was a significant predictor with longer OS compared to decitabine or low dose cytarabine for a given response rate (P < 0.005). Linear regression analysis indicated that the correlation of both CRi or better rates and CR rates with median OS was higher than that of ORR with median OS. The final model showed a strong correlation between CRi or better rates and median OS (R2=0.66). Conclusion: Significant correlation between CRi or better rates and median OS in AML highlights the potential for CRi or better rate, in addition to CR rate, to serve as surrogate markers for median OS.

Venetoclax (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.

This work presents an end-to-end approach for assessing the absolute bioavailability of highly hydrophobic, poorly water-soluble compounds that exhibit high nonspecific binding using venetoclax as a model drug. The approach utilizes a stable labeled i.v. microdose and requires fewer resources compared with traditional approaches that use radioactive 14 C-labeled compounds. The stable labeled venetoclax and internal standard were synthesized, then an i.v. formulation was developed. In the clinical study, female subjects received a single oral dose of venetoclax 100 mg followed by a 100-µg i.v. dose of cold-labeled 13 C-venetoclax at the oral time of maximum concentration (Tmax ). The i.v. microdose was prepared as an extemporaneous, sterile compounded solution on the dosing day by pharmacists at the clinical site. Several measures were taken to ensure the sterility and safety of the i.v. preparation. A sensitive liquid chromatography-tandem mass spectrometry method was developed to allow the detection of plasma levels from the i.v. microdose. Plasma samples were collected through 72 h, and pharmacokinetic parameters were estimated using noncompartmental methods. Postdosing sample analysis demonstrated the consistency of the preparations and allowed the precise calculation of the pharmacokinetic parameters based on the actual injected dose. The absolute bioavailability of venetoclax was estimated at 5.4% under fasting conditions. Venetoclax extraction ratio was estimated to be 0.06 suggesting that the fraction transferred from the enterocytes into the liver is limiting venetoclax bioavailability. The proposed framework can be applied to other highly hydrophobic, poorly water-soluble compounds that exhibit high nonspecific binding to support the understanding of their absorption and disposition mechanisms and guide formulation development.

Venetoclax is an approved BCL-2 inhibitor, currently under evaluation in different hematological malignancies in adult and pediatric populations. Venetoclax is available as 10, 50, and 100 mg tablets. To provide an alternative to patients who find taking the commonly prescribed 100 mg tablet a challenge, the interchangeability of lower-strength tablets with the 100 mg tablet was investigated. Additionally, newly developed oral suspension powder formulations to facilitate dosing in pediatrics were evaluated.

Outcomes remain poor in patients with diffuse large B cell lymphoma (DLBCL) who overexpress BCL-2 protein. We present population pharmacokinetics (PopPK) and exposure-response (ER) analyses for venetoclax (a selective BCL-2 inhibitor) administered with rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in patients with relapsed/refractory (R/R) and previously untreated (1L) non-Hodgkin lymphoma (NHL) from the phase 1b/2 CAVALLI study, to confirm dose selection for future studies.

We previously reported a 44% overall response rate (ORR) with the oral BCL-2 inhibitor venetoclax in a phase I study of relapsed/refractory non-Hodgkin lymphoma (NHL). Complete response (CR) was observed in patients with mantle cell lymphoma [(MCL), 21%, n = 6/28] and follicular lymphoma [(FL), 17%, n = 5/29], and partial response (PR) noted in several patients with Waldenström macroglobulinemia (WM), and marginal zone lymphoma (MZL). Here, we report the long-term outcomes of these four cohorts.

Non-Hodgkin lymphoma (NHL) is a group of lymphoproliferative malignancies with varying treatment responses and progression-free survival (PFS) times. The objective of this study was to quantify the effect of treatment and patient-population characteristics on PFS in patients with NHL.

This study aims to investigate pharmacokinetics (PK) and exposure-response parameters of the 400 mg once-daily venetoclax dose regimen in combination with obinutuzumab, which was approved for the first-line (1L) treatment of chronic lymphocytic leukemia (CLL) based on data from the phase 3 CLL14 study and the phase 1b dose-finding GP28331 study.