The Ministry of Food and Drug Safety (MFDS)'s Central Pharmaceutical Affairs Review Committee has indicated the possibility of conditional approval for Eli Lilly’s lymphoma treatment, "Jaypirca," which is currently in Phase 3 clinical trials. If approved, it could become the third Bruton's tyrosine kinase (BTK) inhibitor available in South Korea, drawing significant interest within the medical community.

The committee recently evaluated the validity of submitted data supporting the orphan drug designation for mantle cell lymphoma (MCL), with Eli Lilly’s "Jaypirca" (pirtobrutinib) being the focal point. The drug is intended for the treatment of relapsed or refractory MCL, a rare form of non-Hodgkin's lymphoma characterized by chromosomal mutations leading to the overexpression of cell cycle-regulating proteins.

Mantle cell lymphoma, accounting for approximately 3% of the 5,600 annual non-Hodgkin's lymphoma cases in South Korea, typically presents at an advanced stage with a poor prognosis. The average survival rate for MCL patients remains under two years, highlighting the need for effective treatment options. Current therapies often include hematopoietic stem cell transplantation and BTK inhibitors like Janssen's "Imbruvica" (ibrutinib) and BeiGene's "Brukinsa" (zanubrutinib), the only BTK inhibitors currently approved for MCL in the country.

During the committee’s deliberations, the focus was on whether Jaypirca should receive conditional approval based on existing Phase 2 data, with the submission of Phase 3 trial results as a post-approval requirement. There was debate regarding the applicability of the ongoing global Phase 3 trial data due to differences in patient populations.

One member proposed that, considering the rarity of MCL and the challenges of conducting controlled trials exclusively with South Korean patients relapsed after BTK inhibitor therapy, conditional approval could be granted if supplemented with long-term observational studies.

Another member suggested that the clinical data from the Phase 2 trial might suffice in place of Phase 3 results. However, the majority of committee members emphasized the need for Phase 3 trials, citing concerns about data insufficiency in fully assessing the drug’s efficacy and benefit-risk profile. "It seems appropriate to impose the completion of a Phase 3 clinical trial as a condition for approval," one member stated, underscoring the importance of robust data, especially given past inconsistencies between objective response rates (ORR) and overall survival (OS) in similar treatments.

The ongoing "BRUIN-MCL-321" study, which measures progression-free survival (PFS), was highlighted as critical for confirming the drug’s efficacy. The committee largely agreed that conditional approval should be granted with the stipulation that these results be submitted post-approval.

The advisory committee concluded that conditional approval, with a requirement to submit Phase 3 data, would be appropriate. This decision increases the likelihood of a new treatment option for MCL, a disease with significant unmet medical needs. The focus now shifts to how reimbursement and competition among BTK inhibitors will evolve following potential approval.