FDA Officially Approves Selpercatinib for RET Fusion+ Thyroid Cancer

On June 12, 2024, the FDA granted traditional approval to selpercatinib (Retevmo) for the treatment of for adult and pediatric patients 2 years of age and older with advanced or metastatic RET fusion-positive thyroid cancer who require systemic therapy and who are radioactive iodine (RAI)-refractory.

In 2020, the FDA granted accelerated approval to the drug based on findings from the LIBRETTO-001 study (NCT03157128) which showed the overall response rates (ORR) to be 85% (95% CI, 71%-94%) among those previously treated with systemic therapy (n = 41) and 96% (95% CI, 79%-100%) for patients who were naive to systemic therapy (n = 24). In the previously treated and systemic treatment-naive populations, the median durations of response (DOR) were 26.7 months (95% CI, 12.1-not evaluable [NE]) and NE (95% CI, 42.8-NE), respectively.

Further, data from the LIBRETTO-121 (NCT03899792) study continue to support the agent, specifically ORR and DOR data from 10 pediatric and young adult patients with RET fusion-positive thyroid cancer. In these patients, the ORR was 60% (95% CI, 26%-88%), and 83% of patients had an observed duration of response at least 12 months.

Here, Francis P. Worden, MD, professor of medicine at the University of Michigan Rogel Cancer Center, Ann Arbor, Michigan, provides a brief overview of this approval and what it means for patients with RET fusion-positive thyroid cancer.

Transcription:

0:09 | We have published data from the LIBRETTO study in both medullary thyroid cancer and in the differentiated thyroid cancers that are refractory to iodine. And so as mentioned earlier, it is important that we do next-generation sequencing on patients who are RAI-refractory to look for driver mutations such as RET fusions. And if they are present and we are ready to treat patients, that would be the drug of choice.

0:50 | The reason being is that their response rates were excellent and close to 75%, and the duration of response and survival were also prolonged. So this FDA indication actually is a game changer for those patients who have these fusions, meaning that this should be frontline therapy for those patients who are refractory to iodine and actually have that particular driver mutation or fusion.