Avelumab, an anti-PD-L1 antibody, in patients with locally advanced or metastatic breast cancer: a phase 1b JAVELIN Solid Tumor study

PURPOSE: Agents targeting programmed death receptor 1 (PD-1) or its ligand (PD-L1) have shown antitumor activity in the treatment of metastatic breast cancer (MBC). The aim of this study was to assess the activity of avelumab, a PD-L1 inhibitor, in patients with MBC. METHODS: In a phase 1 trial (JAVELIN Solid Tumor; NCT01772004), patients with MBC refractory to or progressing after standard-of-care therapy received avelumab intravenously 10 mg/kg every 2 weeks. Tumors were assessed every 6 weeks by RECIST v1.1. Adverse events (AEs) were graded by NCI-CTCAE v4.0. Membrane PD-L1 expression was assessed by immunohistochemistry (Dako PD-L1 IHC 73-10 pharmDx). RESULTS: A total of 168 patients with MBC, including 58 patients with triple-negative breast cancer (TNBC), were treated with avelumab for 2-50 weeks and followed for 6-15 months. Patients were heavily pretreated with a median of three prior therapies for metastatic or locally advanced disease. Grade >/= 3 treatment-related AEs occurred in 13.7% of patients, including two treatment-related deaths. The confirmed objective response rate (ORR) was 3.0% overall (one complete response and four partial responses) and 5.2% in patients with TNBC. A trend toward a higher ORR was seen in patients with PD-L1+ versus PD-L1- tumor-associated immune cells in the overall population (16.7% vs. 1.6%) and in the TNBC subgroup (22.2% vs. 2.6%). CONCLUSION: Avelumab showed an acceptable safety profile and clinical activity in a subset of patients with MBC. PD-L1 expression in tumor-associated immune cells may be associated with a higher probability of clinical response to avelumab in MBC

Absence of interaction of cabazitaxel on the pharmacokinetics of midazolam: Results of a drug–drug interaction study in patients with advanced solid tumors.

126 Background: Cabazitaxel (Cbz) is approved in combination with prednisone/prednisolone for the treatment of men with hormone-refractory metastatic prostate cancer previously treated with a docetaxel-containing treatment regimen. In vitro studies showed that Cbz is mainly metabolized through CYP3A, resulting in inhibition of this family of enzymes. Midazolam (Mdz) is primarily metabolized by CYP3A4. We aimed to determine the effect of Cbz on CYP3A activity by comparing the pharmacokinetic (PK) properties of Mdz when administered alone and following co-administration with Cbz. Methods: An ongoing safety and PK study of Cbz in patients with metastatic or locally advanced solid tumors and varying degrees of hepatic impairment (NCT01140607) included a cohort with normal hepatic function to assess the effect of a single Cbz dose on the PK profile of a single dose of Mdz. This was an open-label, two-period, fixed-sequence study in patients aged between 45 and 60 years with advanced solid tumors and normal hepatic function. A single dose of Mdz (2 mg) was administered orally alone (Day –1) and at the end of a 1-hour infusion of Cbz (25 mg/m2) (Day 1), with a 24-hour interval between the two administrations of Mdz. Endpoints included AUC and AUClastof Mdz with and without Cbz administration, and safety evaluations. Results: Of the 13 patients enrolled and treated in the cohort, 11 patients were included in the PK analysis. Exposure (AUC and AUClast) and other PK parameters after a single administration of Mdz alone and in combination with Cbz (Day 1) were similar. The AUC ratio for Mdz administered alone or with Cbz was 0.97 (90% CI: 0.76–1.23). The AUClast ratio for Mdz administered alone or with Cbz was 1.04 (90% CI: 0.81–1.34). All 13 patients had ≥1 adverse event (AE), 11 (84.6%) experienced a Grade 3–4 AE, and 4 (30.8%) experienced a serious AE. The majority of Grade 3–4 AEs were haematological and no new or unexpected safety findings were observed. Conclusions: In this study, Cbz did not increase the plasma exposure of Mdz. This indicates that Cbz is not a CYP3A inhibitor in the clinical setting and can be administered in combination with drugs metabolized by CYP3A. Clinical trial information: NCT01140607