- Phase 3 subcutaneous teprotumumab (TEPEZZA) achieved a 76.7% proptosis responder rate vs 19.6% placebo (p<0.0001) and mean proptosis reduction −3.17 mm vs −0.80 mm at week 24.
- Dosing: TEPEZZA delivered via on-body injector every two weeks for 12 injections over the 24-week placebo-controlled period.
- Inclusion criteria included moderate-to-severe active TED diagnosed within 15 months and ≥3 mm proptosis from baseline; participants with baseline hearing impairment were allowed.
- Safety consistent with IV profile; common adverse events (≥10%) included muscle spasms, tinnitus, weight decrease, ear discomfort, nausea and diarrhea, with mild-to-moderate injection-site reactions not causing discontinuation.
Key results
Phase 3 subcutaneous teprotumumab (TEPEZZA) via on-body injector met the primary endpoint at Week 24 with a 76.7% proptosis responder rate versus 19.6% for placebo (p<0.0001) and a mean proptosis reduction of −3.17 mm versus −0.80 mm for placebo (p<0.0001).
Trial design and dosing
Randomized, double-masked, placebo-controlled, parallel-group multicenter trial; dosing was subcutaneous delivery via an on-body injector every two weeks for 12 injections over the 24‑week placebo-controlled period.
Population and eligibility
Participants had moderate-to-severe active thyroid eye disease within 15 months and ≥3 mm proptosis from baseline; enrollment allowed participants with baseline hearing impairment.
Secondary endpoints and QoL
Statistically significant improvements were reported for overall responder rate, percentage achieving Clinical Activity Score 0 or 1, multiple diplopia measures (including complete responders), and the GO‑QoL appearance subscale; GO‑QoL visual functioning showed a non‑significant numerical trend favoring treatment; full data to be presented at a medical congress.
Safety
Safety was consistent with the IV profile; mild-to-moderate injection‑site reactions occurred without causing discontinuation; common adverse events (≥10%) included muscle spasms, tinnitus, weight decrease, ear discomfort, nausea and diarrhea.
Additional IV study and context
A separate Phase 3b/4 post‑marketing study of IV TEPEZZA evaluated safety/tolerability of 4, 8 and 16 infusions descriptively and observed a risk profile consistent with prior data; IV TEPEZZA was approved in 2020 and has been used in over 25,000 patients globally.
