FDA Approves Blueprint Medicines, Genentech's Gavreto for RET-altered NSCLC

This article has been updated to include information about an FDA-approved companion diagnostic for pralsetinib.

NEW YORK – The US Food and Drug Administration on Friday granted accelerated approval to Blueprint Medicines and Genentech's Gavreto (pralsetinib) for metastatic, RET fusion-positive, non-small cell lung cancer.

In July, Roche said it would pay Blueprint $775 million for certain rights to pralsetinib under a collaboration agreement. Under the terms of their deal, Blueprint and Roche subsidiary Genentech will co-commercialize pralsetinib in the US. Roche will also have exclusive commercialization rights for pralsetinib outside the US, except in China, Hong Kong, Macau, and Taiwan. CStone Pharmaceuticals will retain development and commercialization rights for pralsetinib in greater China under a previous collaboration with Blueprint Medicines. 

The FDA based its approval on the Phase I/II ARROW trial in which pralsetinib-treated patients had an overall response rate of 57 percent and complete response rate of around 6 percent in 87 NSCLC patients who previously received platinum chemotherapy. The median duration of response was not reached by data cutoff. In 27 patients who were treatment naïve, the overall response rate was 70 percent, with 11 percent experiencing a complete response. The most common adverse events were fatigue, constipation, musculoskeletal pain, and hypertension.

Up to 2 percent of NSCLC patients harbor RET fusions. In the ARROW trial, RET fusions were identified via next-generation sequencing of tumor tissue or liquid biopsies, fluorescent in situ hybridization, or other methods.

In announcing pralsetinib's approval on Friday, Blueprint indicated that RET fusion-positive patients should be identified using an FDA-approved test, though at the time the agency didn't say it had approved any such test. Blueprint previously inked a deal with Thermo Fisher Scientific to develop and commercialize its Oncomine Dx Target Test as a companion diagnostic for pralsetinib to identify RET fusions in NSCLC patients.

On Monday, Sept. 8, Thermo Fisher announced that its Oncomine platform, which evaluates 23 genes associated with lung cancer and includes several companion diagnostic indications, has FDA approval to identify NSCLC patients with RET fusions who may be eligible for pralsetinib. 

In August, the FDA approved NGS-based liquid biopsy assays from Guardant Health and Roche subsidiary Foundation Medicine, and Foundation's tissue-based NGS test has been FDA-approved for several years. Although these tests are able to gauge RET fusions in patients, none of these platforms are approved specifically as a companion diagnostic for pralsetinib.

Since the FDA granted accelerated approval to pralsetinib, continued approval of the drug depends on confirmatory clinical benefit data. This is the second drug approval for Blueprint this year. In January, the FDA approved avapritinib (Blueprint Medicines' Ayvakit) for unresectable or metastatic gastrointestinal stromal tumors harboring a PDGFRA exon 18 mutation. 

Blueprint also announced on Friday that the FDA has accepted its new drug application for pralsetinib as a treatment for advanced or metastatic RET-mutant medullary thyroid cancer and RET fusion-positive thyroid cancer. The application has priority review and the agency is expected to make a decision by Feb. 28, 2021.