Sustained response off-treatment in eltrombopag-treated adult patients with ITP who are refractory or relapsed after first-line steroids: Primary, final, and ad-hoc analyses of the Phase II TAPER trial

Immune thrombocytopenia (ITP) is characterized by reduced platelet count due to increased destruction and is categorized according to the time following diagnosis (newly diagnosed, persistent, chronic). First-line corticosteroid therapy is associated with transient response, high relapse rates, and considerable toxicity. TAPER (NCT03524612) is a Phase II, prospective, single-arm trial investigating whether eltrombopag can induce a sustained response off-treatment (SRoT) in adult patients with ITP after first-line corticosteroid failure. This study defines SRoT as an off-treatment period wherein platelet count remains above 30 × 109 /L in the absence of bleeding or rescue therapy. The primary endpoint was the proportion of patients who achieved SRoT until Month 12, which was 30.5% (n = 32/105; p < .0001 testing hypothesis H1: proportion >15%) following eltrombopag tapering and discontinuation, and median SRoT duration was ~8 months until Month 12. Median platelet count increased within 1 month of treatment and remained elevated until Month 12. Quality of life improved within 3 months and was maintained. Headache (21%) was the most common adverse event. None of the 4 deaths reported were considered treatment-related. In summary, ~one-third of patients achieved SRoT until Month 12 following eltrombopag tapering and discontinuation. An ad-hoc early-use analysis, stratified by ITP duration at baseline, assessed initial hematologic responses and safety. Results suggest that eltrombopag has similar efficacy in newly diagnosed and later stages of ITP. In follow-up until Month 24, a median SRoT duration of ~22 months was observed (n = 20). The safety profile was comparable across analyses and ITP duration groups and aligned with its well-established safety profile.

Candidate Bevacizumab Biosimilar CT-P16 versus European Union Reference Bevacizumab in Patients with Metastatic or Recurrent Non-Small Cell Lung Cancer: A Randomized Controlled Trial

BACKGROUND

CT-P16 is a candidate bevacizumab biosimilar.

OBJECTIVE

This double-blind, multicenter, parallel-group, phase III study aimed to establish equivalent efficacy between CT-P16 and European Union-approved reference bevacizumab (EU-bevacizumab) in patients with metastatic or recurrent non-squamous non-small cell lung cancer (nsNSCLC).

PATIENTS AND METHODS

Patients with stage IV or recurrent nsNSCLC were randomized (1:1) to receive CT-P16 or EU-bevacizumab (15 mg/kg every 3 weeks; ≤ 6 cycles) with paclitaxel (200 mg/m²) and carboplatin (area under the curve 6.0; both for 4-6 cycles), as induction therapy. Patients with controlled disease after induction therapy continued with CT-P16 or EU-bevacizumab maintenance therapy. The primary endpoint was objective response rate (ORR) during the induction period. Time-to-event analyses, pharmacokinetics, safety, and immunogenicity were also evaluated. Results obtained after 1 year of follow-up are presented.

RESULTS

Overall, 689 patients were randomized (CT-P16, N = 342; EU-bevacizumab, N = 347). ORR was 42.40% (95% confidence interval [CI] 37.16-47.64) and 42.07% (95% CI 36.88-47.27) for CT-P16 and EU-bevacizumab, respectively. The risk difference (0.40 [95% CI - 7.02 to 7.83]) and risk ratio (1.0136 [90% CI 0.8767-1.1719]) for ORR fell within predefined equivalence margins (- 12.5 to + 12.5%, and 0.7368 to 1.3572, respectively), demonstrating equivalence between CT-P16 and EU-bevacizumab. Median response duration, time to progression, progression-free survival, and overall survival were comparable between treatment groups. Safety profiles were similar: 96.2% (CT-P16) and 93.0% (EU-bevacizumab) of patients experienced treatment-emergent adverse events. Pharmacokinetics and immunogenicity were comparable between groups.

CONCLUSIONS

Equivalent efficacy and similar pharmacokinetics, safety, and immunogenicity support bioequivalence of CT-P16 and EU-bevacizumab in patients with nsNSCLC.

TRIAL REGISTRATION NUMBER

NCT03676192.

Abstract CT551: Randomized phase III study comparing the efficacy and safety of CT-P16, a new biosimilar, to reference bevacizumab (Avastin®) in patients with metastatic or recurrent non-small cell lung cancer (NSCLC)

Background: CT-P16 is a proposed biosimilar to FDA approved reference bevacizumab (BV), namely Avastin®. This trial (NCT03676192) compared the efficacy and safety of CT-P16 and BV in patients with metastatic or recurrent non-squamous NSCLC.

Methods: This double blind, randomized, multicenter study randomly assigned patients to CT-P16 or BV with carboplatin and paclitaxel, up to 6 cycles (Induction Period), followed by maintenance CT-P16 or BV monotherapy until disease progression or intolerable toxicity. The primary endpoint was objective response rate (ORR) during the Induction Period. ORR includes complete or partial responses based on RECIST v1.1 assessed by an independent reviewer. Secondary endpoints were Quality of life (QoL), PK, safety, and immunogenicity.

Results: A total of 689 patients were randomized (CT-P16: 342, BV: 347). The baseline characteristics were well balanced. ORRs were similar between the two treatment arms and the 90% confidence intervals (CIs) for the risk ratio estimate (0.7368, 1.3572) and 95% CIs for risk difference estimate (±12.5%) were within the equivalence margin in both ITT (intent-to-treat) and PP (per-protocol) sets. QoL results (QLQ-C30 and QLQ-LC13) and PK parameter (Ctrough) were comparable between the two treatment arms. The overall incidence of treatment-emergent adverse events (TEAEs), serious AEs (TESAEs), AEs leading to discontinuation, and AEs leading to death was similar between the two treatment arms (96.2% vs. 92.4%, 19.4% vs. 20.1%, 15.1% vs. 14.5%, and 6.4% vs. 6.4% for the CT-P16 and BV treatment arm, respectively). The incidence of treatment-emergent anti-drug antibodies was comparable (14.2% vs. 16.0%).

Conclusions: This study demonstrated that CT-P16 is equivalent to BV as measured by ORR in patients with metastatic or recurrent adenocarcinoma of the lung. Other endpoints including PK, QoL, safety and immunogenicity were comparable.

Primary endpoint ITT PP CT-P16 (N=342) BV (N=347) CT-P16 (N=318) BV (N=303) Independent reviewer ORR (%) 95% CI 42.40 (37.16 - 47.64) 42.07 (36.88 - 47.27) 45.28 (39.81 - 50.75) 47.19 (41.57 - 52.82) Risk ratio estimate (90% CI) 1.0136 (0.8767, 1.1719) 0.9662 (0.8387, 1.1132) Risk difference estimate (%) (95% CI) 0.40 (-7.02, 7.83) -1.90 (-9.80, 6.00) Investigator ORR (%) 95% CI 43.86 (38.60 - 49.12) 39.19 (34.06 - 44.33) 46.54 (41.06 - 52.02) 43.89 (38.31 - 49.48) Risk ratio estimate (90% CI) 1.1234 (0.9683, 1.3032) 1.0648 (0.9209, 1.2313) Risk difference estimate (%) (95% CI) 4.87 (-2.53, 12.26) 2.90 (-4.99, 10.79)

Citation Format: Yuichiro Ohe, Igor Bondarenko, Zoran Andric, Yuriy Ostapenko, Tudor Ciuleanu, Fedor Moiseenko, Tamta Makharadze, Sergii Shevnya, Alona Oleksiienko, Eduardo Yañez Ruiz, SungHyun Kim, KeumYoung Ahn, TaeHong Park, Sijin Park, JiEun Lee, MinJi Kim, Claire Verschraegen. Randomized phase III study comparing the efficacy and safety of CT-P16, a new biosimilar, to reference bevacizumab (Avastin®) in patients with metastatic or recurrent non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT551.

Efficacy and Safety of CT-P10 Versus Rituximab in Untreated Low-Tumor-Burden Follicular Lymphoma: Final Results of a Randomized Phase III Study

INTRODUCTION

This double-blind, parallel-group, active-controlled phase III trial (NCT02260804) assessed CT-P10 and rituximab safety and efficacy in patients with previously untreated low-tumor-burden follicular lymphoma (LTBFL), including after a single switch from rituximab to CT-P10.

PATIENTS AND METHODS

LTBFL patients were randomized (1:1) to receive CT-P10 or rituximab (375 mg/m² intravenously; day 1 of 4 7-day cycles). Patients achieving disease control entered a 2-year maintenance period. CT-P10 or rituximab were administered every 8 weeks (6 cycles) in year 1; all patients could receive CT-P10 (every 8 weeks; 6 cycles) in year 2. Secondary endpoints (reported here) were overall response rate (ORR) during the study period, progression-free survival (PFS), time to progression (TTP), and overall survival (OS). Safety and immunogenicity were evaluated.

RESULTS

Between  November 9, 2015 and  January 4, 2018, 258 patients were randomized (130 for CT-P10; 128 for rituximab). ORR was similar between groups over the study period (CT-P10: 88%; rituximab: 87%). After 29.2 months' median follow-up, median PFS, TTP, and OS were not estimable; 24-month Kaplan-Meier estimates suggested similarity between groups. Overall, 114 (CT-P10: 88%), and 104 (rituximab: 81%) patients experienced treatment-emergent adverse events. The single switch was well tolerated.

CONCLUSION

These updated data support therapeutic similarity of CT-P10 and rituximab and support the use of CT-P10 monotherapy for previously untreated LTBFL.

Efficacy, pharmacokinetics, and safety of the biosimilar CT-P10 in comparison with rituximab in patients with previously untreated low-tumour-burden follicular lymphoma: a randomised, double-blind, parallel-group, phase 3 trial

BACKGROUND

Studies in patients with rheumatoid arthritis and advanced follicular lymphoma have shown that CT-P10, a rituximab biosimilar, has equivalent or non-inferior efficacy and pharmacokinetics to rituximab. We aimed to assess the therapeutic equivalence of single-agent CT-P10 and rituximab in patients with newly diagnosed low-tumour burden follicular lymphoma.

METHODS

In this ongoing, randomised, double-blind, parallel-group, active-controlled, phase 3 trial, adult patients (≥18 years) with stage II-IV low-tumour-burden follicular lymphoma were randomly assigned (1:1) using an interactive web or voice response system stratified by region, stage, and age to CT-P10 or US-sourced rituximab. Patients received CT-P10 or rituximab (375 mg/m² intravenous) on day 1 of four 7-day cycles (induction period). Patients who had disease control after the induction period continued to a maintenance period of CT-P10 or rituximab administered every 8 weeks for six cycles and, if completed, a second year of maintenance therapy of additional CT-P10 (every 8 weeks for six cycles) was offered. The study was partially unmasked after database lock (Feb 23, 2018) for all data up to 7 months (before cycle 3 of the maintenance period). The primary endpoint was the proportion of patients who achieved an overall response by 7 months in the intention-to-treat population. Efficacy equivalence was shown if the two-sided 90% CIs for the treatment difference in the proportion of responders between CT-P10 and rituximab was within the equivalence margin of 17%. This trial is registered with ClinicalTrials.gov, number NCT02260804.

FINDINGS

Between Nov 9, 2015, and Jan 4, 2018, 402 patients were assessed for eligibility, of whom 258 were randomly assigned: 130 to CT-P10 and 128 to rituximab. 108 (83%) of 130 patients assigned to CT-P10 and 104 (81%) of 128 assigned to rituximab achieved an overall response by month 7 (treatment difference estimate 1·8%; 90% CI -6·43 to 10·20). Therapeutic equivalence was shown (90% CIs were within the prespecified margin of 17%). The most common grade 3 or 4 treatment-emergent adverse events were decreased neutrophil count (two grade 3 in the CT-P10 group) and neutropenia (one in each group); all other grade 3 or 4 treatment-emergent adverse events occurred in one patient each. Six (5%) of 130 patients who received CT-P10 and three (2%) of 128 who received rituximab experienced at least one treatment-emergent serious adverse event.

INTERPRETATION

CT-P10 was equivalent to rituximab in terms of efficacy and was well tolerated. CT-P10 monotherapy is suggested as a new therapeutic option for patients with low-tumour-burden follicular lymphoma.

FUNDING

Celltrion, Inc.

Evolution of checkpoint inhibitors for the treatment of metastatic gastric cancers: Current status and future perspectives

BACKGROUND

Standard treatment options for patients with advanced gastric or gastroesophageal junction cancer (GC/GEJC) are associated with limited efficacy and some toxicity. Recently, immunotherapy with antibodies that inhibit the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) interaction has emerged as a new treatment option. This manuscript reviews early-phase and late-phase trials of immunotherapy in advanced GC/GEJC.

METHODS

Searches for studies of immunotherapy in GC/GEJC were performed using PubMed, ClinicalTrials.gov, and abstract databases for select annual congresses. Findings were interpreted based on expert opinion.

RESULTS

Monotherapy with anti-PD-1/PD-L1 antibodies, including pembrolizumab, nivolumab, avelumab, durvalumab, and atezolizumab, has shown interesting objective response rates (ORRs; 7-26%) across varying GC/GEJC populations, with ORRs potentially higher in PD-L1 + vs PD-L1 - tumors. Safety profiles compare favorably with chemotherapy, with grade ≥3 treatment-related adverse events occurring in 5-17%. Based on a large phase 2 study, pembrolizumab was approved in the United States for third-line treatment of patients with PD-L1 + GC/GEJC. In a phase 3 trial, third-line or later nivolumab increased overall survival vs placebo in an Asian population, leading to regulatory approval in Japan, although other completed phase 3 trials did not show superiority for pembrolizumab or avelumab monotherapy vs chemotherapy. Other trials in advanced GC/GEJC are assessing various anti-PD-1/PD-L1-based strategies, including administration in first-line and later-line settings and as combination (with chemotherapy or agents targeting other immune checkpoint proteins, eg, CTLA-4, LAG-3, and IDO) or switch-maintenance regimens.

CONCLUSIONS

Anti-PD-1/PD-L1 antibodies have shown encouraging clinical activity in advanced GC/GEJC. Results from ongoing phase 3 trials are needed to further evaluate the potential roles of these agents within the continuum of care.