Pralsetinib: chemical and therapeutic development with FDA authorization for the management of RET fusion-positive non-small-cell lung cancers.

Pralsetinib (PRL) is a selective Rearranged during Transfection (RET) inhibitor, developed by Blueprint Medicines Corporation for the treatment of RET fusion non-small-cell lung cancer (NSCLC), papillary thyroid cancer (PTC), and medullary thyroid carcinoma (MTC). RET is a known proto-oncogene found in NSCLC, PTC, and MTC. PRL was recently granted accelerated USFDA approval with the brand name GAVRETO™ on 4 September 2020 to treat metastatic RET fusion-positive NSCLC and was updated on 1 December 2020 with the addition of advanced and metastatic RET-altered MTC and PTC in the USA. On 19 November 2021, the European Commission granted conditional marketing authorization to PRL for use as a single agent in adult patients with RET fusion-positive advanced NSCLC. They were not previously treated with an RET inhibitor. This review article summarizes the milestones in the development of PRL, chemistry, chemical (synthesis) research and development, characterization and identification of PRL-resistant RET mutants, the structural basis of resistance to PRL, mechanism of action, pharmacokinetics, pharmacodynamic, adverse effects, and regulatory status, including ongoing clinical trial of PRL and other potential drug candidates, leading to this first approval of PRL for the treatment of various solid tumors (RET fusion NSCLC, MTC, and PTC).

Ali F ，Neha K ，Chauhan G 《-》

Pralsetinib: First Approval.

Markham A 《-》

The budget impact of adding pralsetinib to a US health plan formulary for treatment of non-small cell lung cancer and thyroid cancer with RET alterations.

Duff S ，Bargiacchi F ，Norregaard C ，Brener M ，Sullivan E ... -  《-》

FDA Approval Summary: Pralsetinib for the Treatment of Lung and Thyroid Cancers With RET Gene Mutations or Fusions.

The FDA granted accelerated approval for pralsetinib on September 4, 2020 for non-small cell lung cancer (NSCLC) and December 1, 2020 for thyroid cancer, for: (i) adult patients with metastatic RET fusion-positive NSCLC, (ii) adult and pediatric patients ≥12 years of age with advanced or metastatic RET-mutant medullary thyroid cancer who require systemic therapy, and (iii) adult and pediatric patients ≥12 years of age with advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine refractory (if radioactive iodine is appropriate). Approval was based on the results of a multicenter, open-label, multi-cohort clinical trial (ARROW, NCT03037385), demonstrating substantial overall response rates (ORR) and durable responses in patients with RET-altered tumors. ORRs within the approved patient populations ranged from 57% [95% confidence interval (CI), 46-68] in patients with RET fusion-positive NSCLC previously treated with platinum chemotherapy to 89% (95% CI, 52-100) in patients with RET fusion-positive thyroid cancer, with response duration of at least 6 months in most responders. The product label includes warnings and precautions for pneumonitis, hypertension, hepatotoxicity, hemorrhagic events, tumor lysis syndrome, risk of impaired wound healing, and embryo-fetal toxicity. This article summarizes the major considerations during FDA review leading to the approval of pralsetinib.

Kim J ，Bradford D ，Larkins E ，Pai-Scherf LH ，Chatterjee S ，Mishra-Kalyani PS ，Wearne E ，Helms WS ，Ayyoub A ，Bi Y ，Sun J ，Charlab R ，Liu J ，Zhao H ，Liang D ，Ghosh S ，Philip R ，Pazdur R ，Theoret MR ，Beaver JA ，Singh H ... -  《-》

Pralsetinib for RET fusion-positive non-small-cell lung cancer (ARROW): a multi-cohort, open-label, phase 1/2 study.

Oncogenic alterations in RET have been identified in multiple tumour types, including 1-2% of non-small-cell lung cancers (NSCLCs). We aimed to assess the safety, tolerability, and antitumour activity of pralsetinib, a highly potent, oral, selective RET inhibitor, in patients with RET fusion-positive NSCLC. ARROW is a multi-cohort, open-label, phase 1/2 study done at 71 sites (community and academic cancer centres) in 13 countries (Belgium, China, France, Germany, Hong Kong, Italy, Netherlands, Singapore, South Korea, Spain, Taiwan, the UK, and the USA). Patients aged 18 years or older with locally advanced or metastatic solid tumours, including RET fusion-positive NSCLC, and an Eastern Cooperative Oncology Group performance status of 0-2 (later limited to 0-1 in a protocol amendment) were enrolled. In phase 2, patients received 400 mg once-daily oral pralsetinib, and could continue treatment until disease progression, intolerance, withdrawal of consent, or investigator decision. Phase 2 primary endpoints were overall response rate (according to Response Evaluation Criteria in Solid Tumours version 1·1 and assessed by blinded independent central review) and safety. Tumour response was assessed in patients with RET fusion-positive NSCLC and centrally adjudicated baseline measurable disease who had received platinum-based chemotherapy or were treatment-naive because they were ineligible for standard therapy. This ongoing study is registered with ClinicalTrials.gov, NCT03037385, and enrolment of patients with treatment-naive RET fusion-positive NSCLC was ongoing at the time of this interim analysis. Of 233 patients with RET fusion-positive NSCLC enrolled between March 17, 2017, and May 22, 2020 (data cutoff), 92 with previous platinum-based chemotherapy and 29 who were treatment-naive received pralsetinib before July 11, 2019 (efficacy enrolment cutoff); 87 previously treated patients and 27 treatment-naive patients had centrally adjudicated baseline measurable disease. Overall responses were recorded in 53 (61%; 95% CI 50-71) of 87 patients with previous platinum-based chemotherapy, including five (6%) patients with a complete response; and 19 (70%; 50-86) of 27 treatment-naive patients, including three (11%) with a complete response. In 233 patients with RET fusion-positive NSCLC, common grade 3 or worse treatment-related adverse events were neutropenia (43 patients [18%]), hypertension (26 [11%]), and anaemia (24 [10%]); there were no treatment-related deaths in this population. Pralsetinib is a new, well-tolerated, promising, once-daily oral treatment option for patients with RET fusion-positive NSCLC. Blueprint Medicines.

Gainor JF ，Curigliano G ，Kim DW ，Lee DH ，Besse B ，Baik CS ，Doebele RC ，Cassier PA ，Lopes G ，Tan DSW ，Garralda E ，Paz-Ares LG ，Cho BC ，Gadgeel SM ，Thomas M ，Liu SV ，Taylor MH ，Mansfield AS ，Zhu VW ，Clifford C ，Zhang H ，Palmer M ，Green J ，Turner CD ，Subbiah V ... -  《-》