Page updated ·next FDA decision on the calendar·Data as of Oct 11, 2026 9:31 PM ET
✓ APPROVED
MIPLYFFA (MY-PLY-FAH) (arimoclomol) was approved by the FDA for Niemann-Pick disease Type C (NPC); the approval was announced on June 8, 2026.
Ligand Pharmaceuticals Incorporated, MIPLYFFA (MY-PLY-FAH) (arimoclomol) · Niemann-Pick disease Type C (NPC).
Run-up into the decision (T-120 → T+5)
Daily close, T-120 (12/22/25) through T+5. Run-up high $241.79 on 4/28/26, low $181.65 on 2/17/26 (T-120 to T-1). FDA decision 6/8/26. Historical price action, not a forecast.
Positioning before the decision
On May 20, 2026, 19 days before the decision date, at-the-money options priced a move of ±9.4% through Jun 18, 2026 (the first listed expiry after the decision; ATM implied volatility 42%). The stock closed +0.3% at the first close across the decision and +7.8% five trading days on. A straddle priced weeks out covers ordinary movement plus the event, so this is the move the options market priced through that expiry, not the event-implied move alone. How this compares across 1,000+ decisions.
Drug / candidateMIPLYFFA (MY-PLY-FAH) (arimoclomol)
CompanyLigand Pharmaceuticals Incorporated
120-day run-up (T-120→T-1)+25.0%
Every FDA approval letter and released Complete Response Letter we hold, by FDA action date: FDA approval letters.
Questions
Was MIPLYFFA (MY-PLY-FAH) (arimoclomol) approved by the FDA?
Yes. The approval of the application for MIPLYFFA (MY-PLY-FAH) (arimoclomol) was announced on June 8, 2026; pdufa.bio holds no FDA record stating the exact day the FDA acted. The primary source is linked on this page.
Which company is behind MIPLYFFA (MY-PLY-FAH) (arimoclomol)?
MIPLYFFA (MY-PLY-FAH) (arimoclomol) is a Ligand Pharmaceuticals Incorporated (LGND) program. The company announced the FDA decision on June 8, 2026; the primary source is linked on this page.
How did LGND stock trade into the FDA decision?
Measured over the 120 trading days before the decision (T-120 to T-1), LGND moved +25.0%. That is the recorded price path into this specific event. Historical measurement, not a prediction, and not investment advice.
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