A phase 1 study of PF-06840003, an oral indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor in patients with recurrent malignant glioma.

Background PF-06840003 is a highly selective indoleamine 2, 3-dioxygenase (IDO1) inhibitor with antitumor effects in preclinical models. This first-in-human phase 1 study evaluated safety, pharmacokinetics/pharmacodynamics, and preliminary efficacy in recurrent malignant glioma to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D). Methods Patients (N = 17) received oral PF-06840003 in four dose-escalation groups: 125 mg once-daily (QD; n = 2); 250 mg QD (n = 4); 250 mg twice-daily (BID; n = 3); 500 mg BID (n = 8). A modified toxicity probability interval method determined the MTD. Results Four patients experienced serious adverse events (SAEs); one with treatment-related SAEs (grade 4 alanine and aspartate aminotransferase elevations). The dose-limiting toxicity (DLT) rate at 500 mg BID was 12.5% (n = 1/8); the MTD was not reached. Following PF-06840003 dosing, median time to maximum plasma concentration for the active enantiomer PF-06840002 was 1.5-3.0 hr and mean elimination half-life was 2 to 4 hr (Cycle 1 Day 1). Urinary recovery of PF-06840002 was low (< 1%). At 500 mg BID, maximum mean percentage inhibition of 13C10 kynurenine vs endogenous kynurenine was 75% vs 24%. PF-06840002 CSF-to-plasma ratio was 1.00. Disease control occurred in eight patients (47%). Mean duration of stable disease (SD) was 32.1 (12.1-72.3) weeks. Two patients with SD discontinued the study at 450 and 561 days and continued PF-06840003 on compassionate use. Conclusion PF­06840003 up to 500 mg BID was generally well tolerated with evidence of a pharmacodynamic effect and durable clinical benefit in a subset of patients with recurrent malignant glioma. ClinicalTrials.gov, NCT02764151, registered April 2016.

Efficacy and Safety of Weekly Somatrogon vs Daily Somatropin in Children With Growth Hormone Deficiency: A Phase 3 Study.

CONTEXT: Somatrogon is a long-acting recombinant human growth hormone (rhGH) in development for once-weekly treatment of children with growth hormone deficiency (GHD). OBJECTIVE: We aimed to compare the efficacy and safety of once-weekly somatrogon with once-daily somatropin in prepubertal children with GHD. METHODS: In this 12-month, open-label, randomized, active-controlled, parallel-group, phase 3 study, participants were randomized 1:1 to receive once-weekly somatrogon (0.66 mg/kg/week) or once-daily somatropin (0.24 mg/kg/week) for 12 months. A total of 228 prepubertal children (boys aged 3-11 years, girls aged 3-10 years) with GHD, impaired height and height velocity (HV), and no prior rhGH treatment were randomized and 224 received ≥1 dose of study treatment (somatrogon: 109; somatropin: 115). The primary endpoint was annualized HV at month 12. RESULTS: HV at month 12 was 10.10 cm/year for somatrogon-treated subjects and 9.78 cm/year for somatropin-treated subjects, with a treatment difference (somatrogon-somatropin) of 0.33 (95% CI: -0.24, 0.89). The lower bound of the 2-sided 95% CI was higher than the prespecified noninferiority margin (-1.8 cm/year), demonstrating noninferiority of once-weekly somatrogon vs daily somatropin. HV at month 6 and change in height standard deviation score at months 6 and 12 were similar between both treatment groups. Both treatments were well tolerated, with a similar percentage of subjects experiencing mild to moderate treatment-emergent adverse events in both groups (somatrogon: 78.9%, somatropin: 79.1%). CONCLUSION: The efficacy of once-weekly somatrogon was noninferior to once-daily somatropin, with similar safety and tolerability profiles. (ClinicalTrials.gov no. NCT02968004).

A Phase I, Open-Label, Dose-Escalation Study of the OX40 Agonist Ivuxolimab in Patients with Locally Advanced or Metastatic Cancers.

PURPOSE: Stimulation of effector T cells is an appealing immunotherapeutic approach in oncology. OX40 (CD134) is a costimulatory receptor expressed on activated CD4+ and CD8+ T cells. Induction of OX40 following antigen recognition results in enhanced T-cell activation, proliferation, and survival, and OX40 targeting shows therapeutic efficacy in preclinical studies. We report the monotherapy dose-escalation portion of a multicenter, phase I trial (NCT02315066) of ivuxolimab (PF-04518600), a fully human immunoglobulin G2 agonistic monoclonal antibody specific for human OX40. PATIENTS AND METHODS: Adult patients (N = 52) with selected locally advanced or metastatic cancers received ivuxolimab 0.01 to 10 mg/kg. Primary endpoints were safety and tolerability. Secondary/exploratory endpoints included preliminary assessment of antitumor activity and biomarker analyses. RESULTS: The most common all-causality adverse events were fatigue (46.2%), nausea (28.8%), and decreased appetite (25.0%). Of 31 treatment-related adverse events, 30 (96.8%) were grade ≤2. No dose-limiting toxicities occurred. Ivuxolimab exposure increased in a dose-proportionate manner from 0.3 to 10 mg/kg. Full peripheral blood target engagement occurred at ≥0.3 mg/kg. Three (5.8%) patients achieved a partial response, and disease control was achieved in 56% of patients. Increased CD4+ central memory T-cell proliferation and activation, and clonal expansion of CD4+ and CD8+ T cells in peripheral blood were observed at 0.1 to 3.0 mg/kg. Increased immune cell infiltrate and OX40 expression were evident in on-treatment tumor biopsies. CONCLUSIONS: Ivuxolimab was generally well tolerated with on-target immune activation at clinically relevant doses, showed preliminary antitumor activity, and may serve as a partner for combination studies.