Company: SION
Filing Date: 2025-02-03
Form Type: S-1/A
Source: 0001193125-25-018825
Chunk: 210

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-02-03
Form: S-1/A
Chunk 210
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 may lead to improvement in serious
outcomes and evidence of safety and effectiveness in a new subpopulation. A priority review designation is intended to direct overall attention and resources to the evaluation of such applications and to shorten the FDA’s goal for taking action
on a marketing application from ten months to six months for an NDA for a new molecular entity from the date of filing. If criteria are not met for priority review, the application for a new molecular entity is subject to the standard FDA review
period of ten months after FDA accepts the application for filing. Priority review designation does not change the scientific/medical standard for approval or the quality of evidence necessary to support approval.

A product may also be eligible for accelerated approval if it treats a serious or life-threatening disease or condition, generally provides a meaningful
advantage over available therapies and demonstrates an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit, or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality
(“IMM”) that is reasonably likely to predict an effect on IMM or other clinical benefit, taking into account the severity, rarity or prevalence of the condition and the availability or lack of alternative treatments. Accelerated approval
by the FDA is generally contingent on a sponsor’s agreement to conduct, in an adequate and diligent manner, additional post-approval confirmatory studies to verify and describe the product’s clinical benefit. These confirmatory trials must
be completed with due diligence, and, under the Food and Drug Omnibus Reform Act of 2022 (“FDORA”), the FDA is now permitted to require, as appropriate, that such trials be underway prior to approval or within a specific time period after
the date of approval for a product granted accelerated approval. Under FDORA, the FDA has increased authority for expedited procedures to withdraw the product from the market (and withdraw its approval). As a result, a product candidate approved on
this basis is subject to rigorous post-marketing compliance requirements, including the completion of Phase 4 or post-approval clinical trials to confirm the effect on the clinical endpoint. Failure to conduct required post-approval studies, or
confirm a clinical benefit during post-marketing studies, could result in the FDA’s withdrawal of the approval and require the withdrawal of the product from the market on an expedited basis. All promotional materials for product candidates
approved under accelerated regulations are subject to prior review by the FDA.

Even if a product qualifies for one or more of these programs, the
FDA may later decide that the product no longer