Safety, antitumor activity, and pharmacokinetics of dostarlimab, an anti-PD-1, in patients with advanced solid tumors: a dose-escalation phase 1 trial.

PURPOSE: New immuno-oncology therapies targeting programmed cell death receptor 1 (PD-1) have improved patient outcomes in a broad range of cancers. The objective of this analysis was to evaluate the PK, pharmacodynamics (PDy), and safety of dostarlimab monotherapy in adult patients with previously-treated advanced solid tumors who participated in parts 1 and 2A of the phase 1 GARNET study. METHODS: Part 1 featured a 3 + 3 weight-based dose-escalation study, in which 21 patients received dostarlimab 1, 3, or 10 mg/kg intravenously every 2 weeks. The 2 fixed-dose nonweight-based dosing regimens of dostarlimab 500 mg every 3 weeks (Q3W) and 1000 mg every 6 weeks (Q6W) were evaluated using a modified 6 + 6 design in part 2A (n = 13). In parts 1 and 2A, treatment with dostarlimab could continue for up to 2 years or until progression, unacceptable toxicity, patient withdrawal, investigator's decision, or death. RESULTS: The dostarlimab PK profile was dose proportional, and maximal achievable receptor occupancy (RO) was observed at all dose levels in the weight-based and fixed-dose cohorts. Trough dostarlimab concentration after administration of dostarlimab 500 mg Q3W was similar to that after dostarlimab 1000 mg Q6W, the values of which (≈40 µg/mL) projected well above the lowest dostarlimab concentration required for full peripheral RO. No dose-limiting toxicities were observed. CONCLUSIONS: Dostarlimab demonstrated consistent and predictable PK and associated PDy. The observed safety profile was acceptable and characteristic of the anti-PD-1 drug class. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02715284. Registration date: March 9, 2016.

Correction to: Phase Ib/II study of gemcitabine, nab-paclitaxel, and pembrolizumab in metastatic pancreatic adenocarcinoma.

The authors would like to note an error in Figures 1 and 2 of this paper. The graph in Figure 1 incorrectly reflected the overall survival (OS), when it should have displayed the progression-free survival (PFS). The caption and median PFS values were correct.

Phase Ib/II study of gemcitabine, nab-paclitaxel, and pembrolizumab in metastatic pancreatic adenocarcinoma.

Background A single center phase Ib/II study of gemcitabine, nab-paclitaxel, and pembrolizumab (GNP) to evaluate the safety and efficacy in metastatic pancreatic adenocarcinoma (PDAC) was conducted (NCT02331251). Methods PDAC patients (pts) with measurable disease, biopsy proven metastasis, adequate laboratory tests, and KPS ≥ 70% received GNP until progression or toxicity. Safety monitoring, RECIST 1.1, and irRECIST assessments were conducted. Response imaging was performed prior to cycle 4, then every 3 months. Changes in tumor cell-free DNA copy number instability (CNI) was retrospectively evaluated. Results 17 pts. with a median age of 56 were treated. 11 were women and all had a KPS of at least 80%. Grade 3 events occurred in 53% of patients. The phase II portion was completed for chemotherapy naïve PDAC pts. Of the 11 evaluable chemotherapy naïve PDAC, the disease control rate (partial response [PR] + stable disease[SD]) was 100%. There were 3 with PR on treatment for 8+, ~11, and 15 months; respectively. The primary endpoint of >15% complete response was not met. The median progression-free survival (PFS) and overall survival (OS) was 9.1 and 15.0 months for chemotherapy naïve treated patients. Of 9 patients evaluable for CNI change, a greater reduction in CNI correlated with longer PFS and improved OS. Conclusions GNP can be safely given to chemotherapy naïve PDAC patients. Efficacy appears to be slightly improved over previously reported results for standard weekly × 3 every 28 day gemcitabine and nab-paclitaxel dosing. CNI change may be prognostic for OS.

A phase Ib study of pembrolizumab plus chemotherapy in patients with advanced cancer (PembroPlus).

BACKGROUND: Pembrolizumab (P) is an anti-PD-1 antibody that blocks the interaction between programmed cell death protein 1 (PD-1) on T-cells and PD-L1 and PD-L2 on tumour cells. A phase Ib trial of P plus chemotherapy was undertaken to evaluate the safety and efficacy. METHODS: Patients with advanced, metastatic solid tumours were enrolled onto one of six treatment arms. Pembrolizumab was given: with gemcitabine (G), G+docetaxel (D), G+nab-paclitaxel (NP), G+vinorelbine (V) or irinotecan (I) until progression or toxicity, or with liposomal doxorubicin (LD) for up to 15 cycles, progression or toxicity. Safety monitoring and response assessments were conducted. RESULTS: Forty-nine patients were enrolled and treated. The most common adverse events were transaminitis, cytopenias, rash, diarrhoea, fatigue, nausea and vomiting. Arm 2 was closed due to poor accrual. The recommended phase II dose (RP2D) was determined for Arms 1, 3a, 4, 5 and 6. There were eight partial responses across multiple tumour types. CONCLUSIONS: Standard dose P can be safely combined with G, G+NP, G+V, I and LD. Efficacy was observed in multiple tumour types and evaluation to determine if response and duration of response are more robust than what would be expected for chemotherapy or immunotherapy alone requires further validation.

Safety, Pharmacokinetics, and Pharmacodynamics of a Humanized Anti-Semaphorin 4D Antibody, in a First-In-Human Study of Patients with Advanced Solid Tumors.

PURPOSE: Study objectives included evaluating the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and antitumor activity of VX15/2503 in advanced solid tumor patients. EXPERIMENTAL DESIGN: Weekly i.v. doses were administered on a 28-day cycle. Safety, immunogenicity, PK, efficacy, T-cell membrane-associated SEMA4D (cSEMA4D) expression and saturation, soluble SEMA4D (sSEMA4D) serum levels, and serum biomarker levels were evaluated. RESULTS: Forty-two patients were enrolled into seven sequential cohorts and an expansion cohort (20 mg/kg). VX15/2503 was well tolerated. Treatment-related adverse events were primarily grade 1 or 2 and included nausea (14.3%) and fatigue (11.9%); arthralgia, decreased appetite, infusion-related reaction, and pyrexia were each 7.3%. One pancreatic cancer patient (15 mg/kg) experienced a Grade 3 dose-limiting toxicity; elevated γ-glutamyl transferase. Complete cSEMA4D saturation was generally observed at serum antibody concentrations ≥ 0.3 µg/mL, resulting in decreased cSEMA4D expression. Soluble SEMA4D levels increased with dose and infusion number. Neutralizing anti-VX15/2503 antibodies led to treatment discontinuation for 1 patient. VX15/2503 Cmax and AUC generally increased with dose and dose number. One patient (20 mg/kg) experienced a partial response, 19 patients (45.2%) exhibited SD for ≥ 8 weeks, and 8 (19%) had SD for ≥ 16 weeks. Subjects with elevated B/T lymphocytes exhibited longer progression-free survival. CONCLUSIONS: VX15/2503 was well tolerated and produced expected PD effects. The correlation between immune cell levels at baseline and progression-free survival is consistent with an immune-mediated mechanism of action. Future investigations will be in combination with immunomodulatory agents.

18-FDG PET/CT assessment of basal cell carcinoma with vismodegib.

The use of 18-fluorodeoxyglucose (FDG) positron emission tomography with computed tomography (PET/CT) in subjects with advanced basal cell carcinoma (BCC) has not been fully explored due to the rarity of disease presentation. This study evaluated PET/CTs from subjects with advanced BCC participating in a phase I dose-escalation clinical trial of vismodegib. Fourteen subjects with BCC were imaged with 18-FDG PET/CT for lesion identification and response categorizing (European Organisation for Research and Treatment for Cancer [EORTC] and PET response criteria in solid tumors [PERCIST] 1.0). Several parameters including metabolic activity of target lesions, site of disease presentation and spread, treatment response, and prognostic significance of metabolic activity following therapy were evaluated. All subjects exhibited at least one hypermetabolic lesion. Most subjects had only four organ systems involved at study enrollment: skin-muscle (93%), lung (57%), lymph nodes (29%), and bone (21%). SUVmax measured across all lesions decreased (median 33%, SD ± 45%) following therapy with metabolic activity normalizing or disappearing in 42% of lesions. No significant difference was observed between EORTC and PERCIST 1.0. Subjects that demonstrated at least a 33% reduction in SUVmax from baseline had a significantly longer progression-free survival (PFS) (median 17 months, 95% confidence interval [CI] ±4 months vs. 9 months, 95% CI ±5 months, P = 0.038) and overall survival (OS) (median 24 months, 95% CI ±4 months vs. 17 months, 95% CI ±13 months, P = 0.019). BCC lesions are hypermetabolic on 18-FDG PET/CT. A decrease in SUVmax was associated with improved PFS and OS. These results further support the incorporation of 18-FDG PET/CT scans in advanced BCC management.

Phase I study of the safety, tolerability and pharmacokinetics of PHA-848125AC, a dual tropomyosin receptor kinase A and cyclin-dependent kinase inhibitor, in patients with advanced solid malignancies.

PURPOSE: This phase I trial assessed the safety, maximally tolerated dose (MTD) and pharmacokinetics of TRKA/CDK inhibitor PHA-848125AC in adult patients with advanced/metastatic solid tumors. PATIENTS AND METHODS: Patients with relapsed or refractory solid tumors, for which no standard therapy existed, were eligible. PHA-848125AC was administered orally in two schedules: daily for 7 consecutive days in 2-week cycles (i.e. 7 days on/7 days off q2wks; S1) or daily for 4 consecutive days a week for 3 weeks in 4-week cycles (i.e. 4 days on/3 days off x 3wks q4wks; S2). RESULTS: Thirty-seven patients were treated in this study, 22 in S1 and 15 in S2. The recommended phase II dose (RP2D) was 150 mg/day for either schedule. The dose-limiting toxicities (DLTs) in S1 included ataxia (Grade 2-4) and tremors (Grade 2-3). In S2, DLTs included tremors (Grade 2-3), elevated lipase (Grade 3), increased creatinine (Grade 2), and nausea and vomiting (Grade 3). These events were all reversible. In S2, out of 14 patients evaluable for efficacy, 2 patients with thymic carcinoma, showed partial response and stable disease was observed in 3 patients. Stable disease was observed in 6 out 14 patients evaluable for efficacy on S1. Drug pharmacokinetics demonstrated a half-life of approximately 33 h, and dose-proportionality with accumulation by a factor of 3 after repeated administrations. CONCLUSION: The RP2D of PHA-848125AC was 150 mg/day on both schedules. Based on the responses noted in thymic carcinoma, a phase II study for patients with that disease is currently enrolling.

Long-term safety, tolerability, and efficacy of vismodegib in two patients with metastatic basal cell carcinoma and basal cell nevus syndrome.

Tumor responses in advanced basal cell carcinoma (BCC) have been observed in clinical trials with vismodegib, a SMO antagonist. The result of SMO antagonism is inhibition Hedgehog Signaling Pathway (HHSP) downstream target genes. HHSP inhibition has been shown to affect stem cells responsible for blood, mammary, and neural development. We report on our experience of treating two patients with advanced BCC participating. These two patients have had no new BCCs develop for at least 2.25 years. Both patients have been receiving ongoing daily treatment with vismodegib for greater than 2.75 years without experiencing any significant side effects. After prolonged continuous daily dosing with a SMO antagonist, we have not observed a significant alteration in hematologic parameters or physical abnormalities of the pectoral regions of two patients with advanced BCC.