RYBREVANT Solution for injection Ref.[28356] Active ingredients: Amivantamab

The exposure-response relationship and time-course of pharmacodynamic response of amivantamab-vmjw have not been fully characterized in patients with NSCLC with EGFR exon 20 insertion mutations.

Amivantamab-vmjw exposures increased proportionally over a dosage range from 350 to 1750 mg (0.25 to 1.25 times the maximum approved recommended dosage). Steady state of amivantamab-vmjw concentrations was achieved by the 9^th infusion. The accumulation ratio at steady state was 2.4.

Distribution

The amivantamab-vmjw mean (± SD) volume of distribution is 5.13 (± 1.78) L.

Elimination

The mean (± SD) clearance of amivantamab-vmjw is 360 (± 144) mL/day and the terminal half-life is 11.3 (± 4.53) days.

Specific Populations

No clinically meaningful differences in the pharmacokinetics of amivantamab-vmjw were observed based on age (range: 32–87 years), sex, race, creatinine clearance (CLcr 29 to 276 mL/min), or mild hepatic impairment [(total bilirubin ≤ ULN and AST > ULN) or (ULN < total bilirubin ≤1.5 times ULN)]. The pharmacokinetics of amivantamab-vmjw have not been studied in patients with severe renal impairment (CLcr 15 to 29 mL/min) or patients with moderate (total bilirubin 1.5 to 3 times ULN) to severe (total bilirubin >3 times ULN) hepatic impairment.

Body Weight

Increases in body weight increased the volume of distribution and clearance of amivantamab-vmjw. Amivantamab-vmjw exposures are 30–40% lower in patients who weighed ≥80 kg compared to patients with body weight < 80 kg at the same dose. Exposures of amivantamab-vmjw were comparable between patients who weighed <80 kg and received 1050 mg dose and patients who weighed ≥ 80 kg and received 1400 mg dose.

No studies have been performed to assess the potential of amivantamab-vmjw for carcinogenicity or genotoxicity. Fertility studies have not been performed to evaluate the potential effects of amivantamab-vmjw. In 6-week and 3-month repeat-dose toxicology studies in monkeys, there were no notable effects in the male and female reproductive organs.

The efficacy of RYBREVANT was evaluated in patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations in a multicenter, open-label, multi-cohort clinical trial (CHRYSALIS, NCT02609776). The study included patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations whose disease had progressed on or after platinum-based chemotherapy. Patients with untreated brain metastases and patients with a history of ILD requiring treatment with prolonged steroids or other immunosuppressive agents within the last 2 years were not eligible for the study.

In the efficacy population, EGFR exon 20 insertion mutation status was determined by prospective local testing using tissue (94%) and/or plasma (6%) samples. Of the 81 patients with EGFR exon 20 insertion mutations, plasma samples from 96% of patients were tested retrospectively using Guardant360 CDx. While 76% of patients had an EGFR exon 20 insertion mutation identified in plasma specimen, 20% did not have an EGFR exon 20 insertion mutation identified in plasma specimen, and 3.7% did not have plasma samples for testing.

Patients received RYBREVANT at 1050 mg (for patient baseline body weight <80 kg) or 1400 mg (for patient baseline body weight ≥80 kg) once weekly for 4 weeks, then every 2 weeks thereafter until disease progression or unacceptable toxicity. The major efficacy outcome measure was overall response rate (ORR) according to Response Evaluation Criteria in Solid Tumors (RECIST v1.1) as evaluated by Blinded Independent Central Review (BICR). An additional efficacy outcome measure was duration of response (DOR) by BICR.

The efficacy population included 81 patients with NSCLC with EGFR exon 20 insertion mutation with measurable disease who were previously treated with platinum-based chemotherapy. The median age was 62 (range: 42 to 84) years, 59% were female; 49% were Asian, 37% were White, 2.5% were Black; 74% had baseline body weight <80 kg; 95% had adenocarcinoma; and 46% had received prior immunotherapy. The median number of prior therapies was 2 (range: 1 to 7). At baseline, 67% had Eastern Cooperative Oncology Group (ECOG) performance status of 1; 53% never smoked; all patients had metastatic disease; and 22% had previously treated brain metastases.

Efficacy results are summarized in Table 9.

Table 9. Efficacy Results for CHRYSALIS:

Based on Kaplan-Meier estimates.
NE = Not Estimable, CI=confidence interval.