Sanofi Gains Japan MHLW Approval for Wayrilz in Immune Thrombocytopenia Following Phase 3 Data

Japan's dual marketing and manufacturing authorization for Wayrilz (rilzabrutinib) signals a CMC and regulatory pathway that rare disease sponsors will study closely. Japan's Ministry of Health, Labour and Welfare (MHLW) granted the combined authorization on June 23, 2026, covering Sanofi's oral reversible Bruton's tyrosine kinase inhibitor for persistent or chronic immune thrombocytopenia (ITP) in patients who have not responded adequately to prior therapy or for whom tolerability is a concern.

The authorization rests on the LUNA 3 phase 3 study (NCT04562766), a 202-patient, placebo-controlled trial evaluating efficacy and safety over a 24-week double-blind period. Wayrilz met both primary and secondary endpoints: 23% of patients in the active arm achieved durable platelet response at week 25 versus 0% in the placebo arm (p<0.0001), with median time to first platelet response of 36 days against a not-reached comparator. Duration of platelet response reached a least-squares mean of 7.0 weeks in the Wayrilz arm versus 0.7 weeks for placebo.

For regulatory affairs leads managing Japan submissions, the MHLW's simultaneous grant of marketing and manufacturing authorization underscores the agency's expectation that CMC documentation and local manufacturing compliance are resolved in parallel with clinical dossiers, not sequentially. Sponsors navigating Japan's Pharmaceutical and Medical Device Act for biologics and small molecules should treat this case as a reference point for aligning Chemistry, Manufacturing and Controls packages with MHLW's manufacturing authorization requirements from the outset of the regulatory strategy.

The most common adverse reactions reported at an incidence of 10% or greater were diarrhea, nausea, headache, abdominal pain, and COVID-19. Quality-of-life data from the ITP Patient Assessment Questionnaire showed a 10.6-point improvement in the Wayrilz arm versus 2.3 points for placebo; Sanofi notes this analysis was descriptive and not powered for statistical significance.

Wayrilz is currently under investigation across additional rare disease indications, including IgG4-related disease, warm autoimmune hemolytic anemia, and sickle cell disease, meaning the manufacturing authorization framework established in Japan for this approval will likely inform subsequent submissions in the same pipeline.

Source: Sanofi via GlobeNewswire, June 23, 2026.