Safety and activity of the anti-CD79B antibody-drug conjugate polatuzumab vedotin in relapsed or refractory B-cell non-Hodgkin lymphoma and chronic lymphocytic leukaemia: a phase 1 study.

BACKGROUND: Patients with relapsed or refractory B-cell non-Hodgkin lymphoma (NHL) have an unfavourable prognosis with few treatment options. Polatuzumab vedotin is an antibody-drug conjugate containing an anti-CD79B monoclonal antibody conjugated to the microtubule-disrupting agent monomethyl auristatin E. We aimed to assess the safety and clinical activity of polatuzumab vedotin in relapsed or refractory B-cell NHL and chronic lymphocytic leukaemia (CLL). METHODS: In this phase 1, multicentre, open-label study, we enrolled patients with documented NHL or CLL expected to express CD79B (confirmation of CD79B expression was not required) and for whom no suitable therapy of curative intent or higher priority existed from 13 centres. The primary endpoints of the study were to assess safety and tolerability, determine the maximum tolerated dose, and identify the recommended phase 2 dose of polatuzumab vedotin as a single agent and in combination with rituximab. A 3 + 3 dose-escalation design was used in which we treated patients with polatuzumab vedotin (0·1-2·4 mg/kg every 21 days) in separate dose-escalation cohorts for NHL and CLL. After determination of the recommended phase 2 dose, we enrolled patients with relapsed or refractory diffuse large B-cell lymphoma and relapsed or refractory indolent NHL into indication-specific cohorts. We also enrolled patients with relapsed or refractory NHL into an additional cohort to assess the feasibility of the combination of polatuzumab vedotin and rituximab 375 mg/m(2). Patients who received any dose of polatuzumab vedotin were available for safety analyses. This study is registered with ClinicalTrials.gov, number NCT01290549. FINDINGS: Between March 21, 2011, and Nov 30, 2012, we enrolled 95 patients (34 to the NHL dose-escalation cohort, 18 to the CLL dose-escalation cohort, 34 with NHL to the expansion cohort at the recommended phase 2 dose, and nine with NHL to the rituximab combination cohort; no expansion cohort of CLL was started due to lack of activity in the dose-escalation cohort). The recommended phase 2 dose in NHL was 2·4 mg/kg as a single agent and in combination with rituximab; the maximum tolerated dose in CLL was 1·0 mg/kg as a result of dose-limiting toxic effects reported in two of five patients given 1·8 mg/kg. Grade 3-4 adverse events were reported in 26 (58%) of 45 patients with NHL treated at the single-agent recommended phase 2 dose, and the most common grade 3-4 adverse events were neutropenia (18 [40%] of 45), anaemia (five [11%]), and peripheral sensory neuropathy (four [9%]). Serious adverse events were reported in 17 (38%) of 45 patients, and included diarrhoea (two patients), lung infection (two patients), disease progression (two patients), and lung disorder (two patients). Seven (77%) of nine patients in the rituximab combination cohort had a grade 3-4 adverse event, with neutropenia (five [56%]), anaemia (two [22%]), and febrile neutropenia (two [22%]) reported in more than one patient. 11 (12%) of 95 patients died during the study: eight with relapsed or refractory diffuse large B-cell lymphoma (due to progressive disease in four patients, infections in three patients [two treatment related], and treatment-related worsening ascites in one patient) and three with relapsed or refractory CLL (due to progressive disease, pulmonary infection, and pneumonia; none thought to be treatment-related). At the recommended phase 2 dose, objective responses were noted in 23 of 42 activity-evaluable patients with NHL given single-agent polatuzumab vedotin (14 of 25 with diffuse large B-cell lymphoma, seven of 15 with indolent NHL, and two with mantle-cell lymphoma) and seven of nine patients treated with polatuzumab vedotin combined with rituximab. No objective responses were observed in patients with CLL. INTERPRETATION: Polatuzumab vedotin has an acceptable safety and tolerability profile in patients with NHL but not in those with CLL. Its clinical activity should be further assessed in NHL. FUNDING: Genentech.

Efficacy and Safety of Rovalpituzumab Tesirine in Third-Line and Beyond Patients with DLL3-Expressing, Relapsed/Refractory Small-Cell Lung Cancer: Results From the Phase II TRINITY Study.

PURPOSE: Although extensive-stage small-cell lung cancer (SCLC) is highly responsive to first-line therapy, virtually all patients develop resistance with short survival. Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate targeting delta-like 3 protein (DLL3). This open-label, single-arm, phase II study (TRINITY) assessed safety and efficacy of Rova-T in patients with DLL3-expressing SCLC in the third-line and beyond (3L+) setting. PATIENTS AND METHODS: Patients with DLL3-expressing SCLC (determined by mouse antibody immunohistochemistry [IHC] assay), and ≥2 prior regimens, received 0.3 mg/kg Rova-T once every 6 weeks for two cycles. During study, a rabbit antibody IHC assay was developed and used for the final analysis, with DLL3-positive and DLL3-high defined as ≥25% and ≥75% of tumor cells positive for DLL3, respectively. The primary endpoints were objective response rate (ORR) and overall survival (OS). RESULTS: Among 339 patients enrolled, 261 (77%) had two prior lines of therapy and 78 (23%) had ≥3. DLL3-high and DLL3-positive tumors by rabbit IHC were seen in 238 (70%) and 287 (85%) patients, respectively. The remaining 52 (15%) were DLL3-negative only by rabbit IHC or had missing results. ORR was 12.4%, 14.3%, and 13.2% in all, DLL3-high, and DLL3-positive patients, respectively. Median OS was 5.6 months in all patients and 5.7 months in DLL3-high patients. The most common adverse events (AE) were fatigue, photosensitivity reaction, and pleural effusion. Grade 3-5 AEs were seen in 213 (63%) patients. CONCLUSIONS: Rova-T is the first targeted agent in SCLC to use DLL3, a novel biomarker. However, results demonstrate modest clinical activity in 3L+ SCLC, with associated toxicities.

Phase I Study of the Anti-CD22 Antibody-Drug Conjugate Pinatuzumab Vedotin with/without Rituximab in Patients with Relapsed/Refractory B-cell Non-Hodgkin Lymphoma.

Purpose: Pinatuzumab vedotin is an antibody-drug conjugate with the potent antimicrotubule agent monomethyl auristatin E (MMAE) conjugated to an anti-CD22 antibody via a protease-cleavable linker. This phase I study determined its recommended phase II dose (RP2D) and evaluated its safety, tolerability, and antitumor activity alone and with rituximab in relapsed/refractory (r/r) non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL).Experimental Design: Patients received escalating doses of pinatuzumab vedotin every 21 days. Clinical activity at the RP2D alone or with rituximab was evaluated in r/r diffuse large B-cell lymphoma (DLBCL) and r/r indolent NHL (iNHL) patients.Results: Seventy-five patients received single-agent pinatuzumab vedotin. The RP2D was 2.4 mg/kg, based on dose-limiting toxicities (DLT) of grade 4 neutropenia >7 days in 1 of 3 patients and grade 4 neutropenia <7 days in 2 of 3 patients treated at 3.2 mg/kg (maximum assessed dose). No DLTs occurred at 2.4 mg/kg. At the RP2D, neutropenia was the most common grade ≥3 adverse event. Peripheral neuropathy-related grade ≥2 adverse events most frequently resulted in treatment discontinuation. Rituximab cotreatment did not impact safety, tolerability, or pharmacokinetics of pinatuzumab vedotin. Unconjugated MMAE exposure was much lower than antibody-conjugated MMAE exposure, without accumulation with repeat dosing. At the RP2D, objective responses were observed in DLBCL (9/25) and iNHL (7/14) patients; 2 of 8 patients treated with pinatuzumab vedotin (RP2D) and rituximab had complete responses. CLL patients showed no objective responses.Conclusions: The RP2D of pinatuzumab vedotin alone and with rituximab was 2.4 mg/kg, which was well tolerated, with encouraging clinical activity in r/r NHL. Clin Cancer Res; 23(5); 1167-76. ©2016 AACR.

Peginterferon alfa-2a does not alter the pharmacokinetics of methadone in patients with chronic hepatitis C undergoing methadone maintenance therapy.

OBJECTIVE: Our objective was to quantify the pharmacokinetics of methadone and the pharmacokinetics and pharmacodynamics of peginterferon alfa-2a (40 kd) in patients with chronic hepatitis C undergoing methadone maintenance therapy. METHODS: Adults with chronic hepatitis C who had been receiving a consistent methadone maintenance regimen for at least 3 months were eligible for this open-label, multicenter, nonrandomized drug interaction study. All patients received 180 microg subcutaneous peginterferon alfa-2a once weekly for 4 weeks and continued their methadone regimen. Serial blood samples were collected at baseline and immediately before and for up to 168 hours after study drug administration for the purposes of quantifying methadone and peginterferon alfa-2a serum concentrations, measuring serum 2',5'-oligoadenylate synthetase activity, and determining hepatitis C virus ribonucleic acid levels. RESULTS: Twenty-four patients were enrolled. Methadone exposure, as measured by maximum serum concentration (C(max)) and area under the concentration-time curve (AUC) normalized to a 100-mg/d dose, after 4 doses of peginterferon alfa-2a increased by 10% to 15% when compared with baseline. The week 4/baseline ratio of the mean C(max) was 1.11 (90% confidence interval [CI], 1.02-1.22), and for AUC from time 0 to 24 hours, the week 4/baseline ratio was 1.15 (90% CI, 1.08-1.23). The mean accumulation ratios (week 4/first dose) for C(max) and AUC from time 0 to 168 hours of peginterferon alfa-2a were 2.1 and 2.3, respectively. CONCLUSIONS: Peginterferon alfa-2a does not appreciably alter the pharmacokinetics of methadone.

A phase 2 study of the BH3 mimetic BCL2 inhibitor navitoclax (ABT-263) with or without rituximab, in previously untreated B-cell chronic lymphocytic leukemia.

We evaluated the safety and biologic activity of the BH3 mimetic protein, navitoclax, combined with rituximab, in comparison to rituximab alone. One hundred and eighteen patients with chronic lymphocytic leukemia (CLL) were randomized to receive eight weekly doses of rituximab (arm A), eight weekly doses of rituximab plus daily navitoclax for 12 weeks (arm B) or eight weekly doses of rituximab plus daily navitoclax until disease progression or unacceptable toxicity (arm C). Investigator-assessed overall response rates (complete [CR] and partial [PR]) were 35% (arm A), 55% (arm B, p = 0.19 vs. A) and 70% (arm C, p = 0.0034 vs. A). Patients with del(17p) or high levels of BCL2 had significantly better clinical responses when treated with navitoclax. Navitoclax in combination with rituximab was well tolerated as initial therapy for patients with CLL, yielded higher response rates than rituximab alone and resulted in prolonged progression-free survival with treatment beyond 12 weeks.