Rare Thyroid Therapeutics International AB

Rare Thyroid Therapeutics (RTT) was a Swedish private clinical-stage company specializing in therapies for rare thyroid hormone signaling disorders, headquartered in Stockholm. Its lead candidate Emcitate (tiratricol) was developed for MCT8 deficiency, a rare congenital disorder affecting ~1 in 70,000 males. RTT was acquired by PledPharma in 2020, giving rise to Egetis Therapeutics. The European Commission approved Emcitate in February 2025 as the first treatment for MCT8 deficiency in the EU.