Rapport's attempt to test epilepsy drug in nerve damage placed on hold by FDA

The FDA has placed a trial of Rapport Therapeutics’ epilepsy drug for a type of nerve pain on hold while the biotech tweaks the study design.

Rapport has been evaluating the TARPγ8-targeting drug, dubbed RAP-219, in a range of conditions like focal epilepsy and bipolar acute mania and as an anti-seizure medication. The biotech had submitted a request to the FDA to launch a phase 2a proof-of-concept trial in diabetic peripheral neuropathic pain (DPNP) but was “recently” notified by the agency that the request had been placed on clinical hold.

The FDA requested “additional information and amendments specific to the protocol design,” said Rapport, which stressed that the hold is specific to the proposed DPNP trial and “has not impacted the company’s ongoing phase 2a trial in focal epilepsy or planned proof-of-concept trial in bipolar disorder.”

“The company believes in its ability to resolve the clinical hold in DPNP and will provide an update on the anticipated timing of the phase 2a trial initiation once available,” Rapport added in its third-quarter earnings release Thursday.

DPNP is nerve pain that affects some people with diabetes, especially damaging nerves in the limbs and extremities.

Boston- and San Diego-based Rapport was launched by Third Rock Ventures in May 2023 with the primary aim of developing RAP-219, which itself originated in Johnson & Johnson’s labs. The fledgling company went on to IPO earlier this year, having claimed that RAP-219 has blockbuster potential in epilepsy.

Part of those IPO proceeds had been earmarked to take another TARPg8 program, dubbed RAP-199, into the clinic for the first time. But Rapport said in this morning’s release that “with growing confidence in RAP-219 and a commitment to disciplined capital allocation, the company is deferring further investment in RAP-199” in order to focus on the three clinical trials of its lead candidate.

Top-line data from the phase 2a trial for the treatment of bipolar acute mania as well as a phase 1 study using positron emission tomography in healthy adults to confirm the parts of the brain affected by RAP-219 are both due to read out in the first quarter of next year. Data from the phase 2 focal epilepsy study are due to follow in mid-2025.

"We are pleased with the progress we’re making with RAP-219, particularly as we continue the execution of our phase 2a proof-of-concept trial in focal epilepsy,” CEO Abraham Ceesay said in the release. 

“The continued learnings from our ongoing clinical activities, including the MAD-2 and PET trials as well as our pharmaceutical development efforts, have only strengthened our confidence in the pipeline-in-a-product potential of RAP-219 as a potentially transformational treatment for focal epilepsy, peripheral neuropathic pain, and bipolar disorder,” Ceesay added.