In a landmark development for precision oncology, the US Food and Drug Administration has approved Eli Lilly's Retevmo (selpercatinib) for treating lung and thyroid cancers harboring RET gene alterations. This approval marks the first therapy specifically targeting RET mutations and fusions in these cancer types.
Breakthrough Clinical Efficacy
The approval is supported by compelling data from the LIBRETTO-001 phase 1/2 trial, where Retevmo demonstrated significant efficacy across multiple patient populations. In RET-positive non-small cell lung cancer (NSCLC), the drug achieved an impressive 84% overall response rate in treatment-naïve patients and 64% in those previously treated with chemotherapy.
The response rates were equally promising in thyroid cancers. Medullary thyroid cancer (MTC) patients showed response rates of 73% in the treatment-naïve group and 69% in previously treated patients. Other thyroid cancer types demonstrated even higher efficacy, with response rates reaching 100% in treatment-naïve patients and 79% in the previously treated group.
Durability of Response
The drug's effectiveness proved sustainable, with a majority of patients maintaining their response for six months or longer. Specifically, 58% of NSCLC patients, 61% of MTC patients, and 75% of other thyroid cancer patients experienced sustained benefits beyond the six-month mark.
Rapid Development Timeline
"Retevmo entered clinical trials in May of 2017 and is now approved less than three years later, representing the most rapid timeline in the development of an oncology medicine with multiple indications," noted Anne White, president of Lilly Oncology. This accelerated development underscores the drug's potential impact on patient care.
Market Impact and Accessibility
Lilly has announced immediate launch plans despite COVID-19 challenges, with pricing set at $20,600 for a 30-day supply, aligned with other biomarker-targeted cancer therapies. Industry analysts project Retevmo could generate over $500 million in annual sales by 2024.
Patient Population and Testing Requirements
The drug addresses significant unmet needs across multiple patient populations, including approximately 2% of NSCLC patients, 20-40% of thyroid cancer cases, and up to 70% of MTC patients with RET alterations. Success will depend on widespread genetic testing to identify eligible patients.
Competitive Landscape
This approval positions Lilly ahead of competitor Blueprint Medicines, whose rival RET inhibitor pralsetinib is currently under regulatory review. Retevmo represents Lilly's second approved drug from its $8 billion Loxo Oncology acquisition, following the earlier success of Vitrakvi for NTRK gene fusion tumors.
