Palvella Therapeutics (PVLA) Study result summary

Study overview and objectives

• Phase III SELVA trial evaluated QTORIN 3.9% rapamycin gel for microcystic lymphatic malformations, a rare, debilitating disease with no FDA-approved therapies and significant impact from birth.

• The study enrolled 51 patients aged three and older, including those with significant disease burden and prior treatment failures; 49 patients aged ≥6 years formed the intent-to-treat population.

• SELVA was a single-arm, baseline-controlled trial with a 24-week efficacy period and an open-label extension.

• Study endpoints were informed by phase II results and patient/clinician input, focusing on both global and specific disease changes.

• Supported by an FDA Orphan Products Grant and received Breakthrough Therapy, Fast Track, and Orphan Drug designations.

Efficacy results

• QTORIN rapamycin achieved a +2.13 mean improvement on the mLM-IGA primary endpoint at week 24 (p<0.001), exceeding predefined efficacy goals.

• 95% of participants improved on the primary endpoint; 86% were rated as much or very much improved.

• All primary, key secondary, and four additional secondary endpoints were met with high statistical significance (all p<0.001), including blinded clinician assessments and patient-reported outcomes.

• Key secondary endpoint (blinded mLM-MCSS) showed a mean improvement of -3.36 (p<0.001).

• High concordance was seen across adult and pediatric patients, time points, and assessment types.

Safety and tolerability

• QTORIN rapamycin was well tolerated in both children and adults, supporting chronic dosing, with no drug-related serious adverse events.

• 70% experienced treatment-emergent adverse events, mostly mild or moderate; most common were application site acne, discoloration, and pruritus.

• Systemic rapamycin levels remained minimal, below two nanograms/mL for all patients at all timepoints.

• Six patients withdrew early; only one discontinuation was possibly related to the drug (lymphorrhea).

• 98% of week 24 completers elected to continue in the extension period, indicating strong retention and perceived benefit.