Clinical pharmacokinetics and pharmacodynamics of ivosidenib in Chinese patients with relapsed or refractory IDH1-mutated acute myeloid leukemia.

PURPOSE: This study aimed to assess the pharmacokinetics (PK) and pharmacodynamics (PD) of ivosidenib in Chinese patients with relapsed or refractory acute myeloid leukemia (R/R AML) carrying the mIDH1 mutation. METHODS: A bridging study (NCT04176393) was conducted involving 29 Chinese patients who received a daily dose of ivosidenib 500 mg in 28-day cycles. Plasma concentrations of ivosidenib and D-2-hydroxyglutarate (2-HG) were measured before and after treatment. Non-compartmental analysis (NCA) was employed to evaluate the PK, and an established population pharmacokinetic (popPK) model developed from non-Chinese patients was externally validated. RESULTS: The findings revealed comparable PD effects of ivosidenib in Chinese patients with mIDH1 R/R AML. After adjusting for concomitant drug effects, PK characteristics were similar between Chinese and non-Chinese patients. Furthermore, the popPK model offered additional insights into the possible causes of the apparent ethnic difference in PK exposure. CONCLUSION: The study indicates that ivosidenib can be used effectively in Chinese patients, and the observed ethnic differences in PK exposure can be explained by concomitant drug effects. The popPK model contributes to a better understanding and optimization of personalized dosing in Chinese patients with mIDH1 R/R AML.

A first-in-human phase 1 study of nofazinlimab, an anti-PD-1 antibody, in advanced solid tumors and in combination with regorafenib in metastatic colorectal cancer.

BACKGROUND: We assessed nofazinlimab, an anti-PD-1 antibody, in solid tumors and combined with regorafenib in metastatic colorectal cancer (mCRC). METHODS: This phase 1 study comprised nofazinlimab dose escalation (phase 1a) and expansion (phase 1b), and regorafenib dose escalation (80 or 120 mg QD, days 1-21 of 28-day cycles) combined with 300-mg nofazinlimab Q4W (part 2a) to determine safety, efficacy, and RP2D. RESULTS: In phase 1a (N = 21), no dose-limiting toxicity occurred from 1 to 10 mg/kg Q3W, with 200 mg Q3W determined as the monotherapy RP2D. In phase 1b (N = 87), 400-mg Q6W and 200-mg Q3W regimens were found comparable. In part 2a (N = 14), both regimens were deemed plausible RP2Ds. Fatigue was the most frequent treatment-emergent adverse event (AE) in this study. Any-grade and grade 3/4 nofazinlimab-related AEs were 71.4% and 14.3%, 56.3% and 5.7%, and 57.1% and 21.4% in phases 1a, 1b, and part 2a, respectively. ORRs were 14.3% and 25.3% in phases 1a and 1b, respectively. In part 2a, no patients had radiological responses. CONCLUSIONS: Nofazinlimab monotherapy was well tolerated and demonstrated preliminary anti-tumor activity in multiple tumor types. Regorafenib plus nofazinlimab had a manageable safety profile but was not associated with any response in mCRC. CLINICAL TRIAL REGISTR ATION: Clinicaltrials.gov (NCT03475251).

Evaluation of Bioequivalence for Avapritinib Tablets in Chinese Participants Under Fasting Conditions Using a Reference-Scaled Average Bioequivalence Method.

This study aimed to assess the bioequivalence of 2 avapritinib tablets formulations. A randomized, open-label, single-center trial was conducted on fasting, healthy Chinese participants. The study utilized a partial replicated design with 3 sequences and 3 periods. Participants were assigned to 1 of 3 sequences, with each sequence receiving the reference formulation twice and the test formulation once. Plasma samples were collected and analyzed to determine pharmacokinetic parameters. The bioequivalence of the 2 avapritinib formulations was assessed using reference-scaled average bioequivalence for the maximum plasma concentration (Cmax) and the average bioequivalence analysis for the area under the concentration-time curve (AUC). Out of 39 participants, 38 completed the study. For Cmax, the 1-sided 95% upper confidence interval (CI) bound from the scaled approach was -0.035 (<0) and the point estimate value was 0.958, falling inside the acceptance range of 0.8-1.25. For both the AUC over all concentrations measured (AUC0-t) and the AUC from time 0 to infinity (AUC0-inf), the 90% CIs of geometric mean ratios (0.87-1.01) also met the bioequivalence criteria of 0.8-1.25. Consequently, the study demonstrated that the 2 avapritinib formulations were bioequivalent under fasting conditions.

Ivosidenib in Chinese patients with relapsed or refractory isocitrate dehydrogenase 1 mutated acute myeloid leukemia: a registry study.

Ivosidenib, an isocitrate dehydrogenase 1 (IDH1) inhibitor, has demonstrated clinical benefits in a pivotal study (AG120-C-001) in patients with IDH1-mutated (mIDH1) acute myeloid leukemia (AML). A registry study (CS3010-101: NCT04176393) was conducted to assess the pharmacokinetic (PK) characteristics, safety, and efficacy of ivosidenib in Chinese patients with relapsed or refractory (R/R) mIDH1 AML. Patients received ivosidenib 500 mg once daily for 28-day cycles until disease progression. Ten subjects underwent intensive PK/progressive disease (PD) assessments. All subjects had the clinical response assessed at screening, every 28 days through month 12, and then every 56 days. Between November 12, 2019, and April 2, 2021, 30 patients were enrolled; 26 (86.7%) had de novo AML and 18 (60.0%) were transfusion-dependent at baseline. Following single and repeated doses of ivosidenib, median time to maximum plasma concentration (T max) was 4.0 and 2.0 hours, respectively. The inter-individual variability of pharmacokinetic exposure was moderate to high (coefficient of variation [CV], 25%-53%). No obvious accumulation was observed after repeated doses at cycle 2 day 1. Regarding the clinical response, the CR + CRh rate was 36.7% (95% confidence interval [CI]: 19.9%-56.1%), the median duration of CR + CRh was 19.7 months (95% CI: 2.9 months-not reached [NR]), and median duration of response (DoR) was 14.3 months (95% CI: 6.4 months-NR). Consistent clinical benefits and safety of ivosidenib were consistently observed at the final data cutoff with median follow-up time 26.0 months, as compared with primary data cutoff, and the data from Chinese R/R mIDH1 AML patients were also consistent with results from pivotal study.