Considerations for the use of the Plausible Mechanism Framework to Develop Individualized Therapies that Target Specific Genetic Conditions with Known Biological Cause; Draft Guidance for Industry

Rejuvenation Technologies, a biotechnology company, supports the draft guidance but requests specific clarifications to ensure the Plausible Mechanism Framework includes therapies for multi-gene convergent conditions like telomere biology disorders. They argue that the current language focusing on single genetic variants might inadvertently exclude treatments that address a common downstream mechanism across multiple genes.

The American Brain Tumor Association (ABTA) supports the draft guidance as a necessary step for developing therapies for rare diseases with unmet needs. However, they request specific language changes to replace "other types" with "any types" of individualized therapies to ensure the framework is not unintentionally restrictive for various therapeutic approaches.

The California Institute for Regenerative Medicine (CIRM), a state agency, supports the draft guidance as a positive regulatory innovation for accelerating the development of genetic medicines for rare diseases. They advocate for specific refinements, including clearer eligibility criteria, flexibility in observational periods for rapidly progressing diseases, and the creation of a unique regulatory designation to ensure consistent FDA interaction.

The N=1 Collaborative (N1C), a nonprofit consortium of clinicians, researchers, and patient advocates, supports the draft guidance as a necessary step for developing individualized therapies for rare genetic diseases. They recommend specific improvements, including making data sharing a requirement, calibrating CMC standards for small-batch manufacturing, expanding the platform concept to multiple genes, and establishing a formal process for developing clinical effectiveness standards.

DEE-P Connections, a caregiver-led collaborative organization representing families affected by Developmental and Epileptic Encephalopathy (DEE), strongly supports the FDA's Plausible Mechanism Framework. They argue that the framework should be improved to better incorporate real-world data, mandate meaningful patient engagement, utilize flexible trial designs, and ensure the use of fit-for-purpose outcome measures for medically fragile populations.

The Cure Sanfilippo Foundation, a nonprofit patient advocacy organization, supports the proposed Plausible Mechanism Framework as a significant step forward for developing therapies for ultra-rare diseases. They request specific clarifications to ensure the framework is inclusive of various therapeutic modalities, uses "fit-for-purpose" natural history data, allows for flexible endpoints, and adopts "right-sized" manufacturing requirements for small patient populations.

flok Health, a patient-led organization for individuals with inherited disorders of protein metabolism, supports the FDA's Plausible Mechanism Framework for individualized therapies. They urge the FDA to incorporate structured real-world data as a foundational evidence stream and to leverage shared mechanisms and platform approaches to improve access for patients with ultra-rare variants.

The Sanfilippo Initiative, representing the Sanfilippo patient community, supports the Plausible Mechanism Framework as a necessary approach for developing therapies for ultra-rare diseases. They urge the FDA to ensure the framework applies to all therapeutic modalities (such as enzyme replacement and small molecules) and to provide flexibility regarding biomarkers and natural history data in small patient populations.

The commenter, a family member affected by a rare genetic disease, supports the proposed Plausible Mechanism Framework because it addresses the unique needs of small populations with monogenic diseases. They specifically advocate for the inclusion of pre-symptomatic carriers in trials and request that patient and family community input be integrated into protocol design.