Egetis Therapeutics AB wins FDA approval for Emcitate in MCT8 deficiency

The first U.S. treatment for excess thyroid hormone in MCT8 deficiency moved toward launch as Egetis Therapeutics AB (publ) STOEGTX said Monday the FDA had approved Emcitate. The company expects the tablets for oral suspension to be commercially available eight to 10 weeks after the Sept. 28 decision.

The approval covers peripheral thyrotoxicosis in adult and pediatric patients with MCT8 deficiency, also called Allan-Herndon-Dudley syndrome. The approved indication does not include the disorder's neurological impairment, and Egetis says Emcitate is not recommended for primary hypothyroidism. FDA also granted Egetis a rare pediatric disease priority review voucher.

Egetis is a Stockholm-based drug developer focused on treatments for rare diseases.

The issuer's Sept. 28 GlobeNewswire release was stamped 5:46 p.m. ET. Nasdaq's EGTX page dates its displayed quote to Sept. 28 at 18:00 CET. That quote predates the announcement and cannot show the market's response. Stockholm trading on Sept. 29 will provide the first regular-session test.

FDA Cites Two Studies of Hormone Levels

The FDA said efficacy was evaluated in an international, randomized, placebo-controlled study and a longer-term open-label study. Across the two studies, patients treated with Emcitate had reductions in excess circulating thyroid hormone and improvements in systolic blood pressure and heart rate. The agency's Sept. 28 announcement did not give an effect size, sample count or p value.

MCT8 deficiency impairs a protein that transports thyroid hormone into the brain, leaving too much of the hormone in the bloodstream. According to the FDA, tiratricol can enter cells without that transporter and reduce the elevated blood levels. The drug is taken once daily as a liquid suspension, by mouth or through a feeding tube.

The FDA identified diarrhea, vomiting, rash and excessive sweating as the most common side effects. It also advised patients taking another thyroid medication to speak with their clinician before starting Emcitate because the two should not be used together. Egetis's prescribing information carries a boxed warning against use for obesity or weight loss.

"Our immediate focus is ensuring that eligible patients can access EMCITATE as quickly as possible," Egetis chief executive Nicklas Westerholm said in the Sept. 28 release.

Egetis has opened its RareLink patient support program and enlisted PANTHERx Rare to support specialty distribution, education and care coordination. Commercial availability remains an eight-to-10-week forecast, while the Sept. 28 announcement gave neither a U.S. list price nor a sales projection.

The Voucher Adds a Separate Asset

Egetis said on Sept. 28 it currently expects to explore monetizing the priority review voucher. A sale could potentially occur in the fourth quarter of 2026, subject to market conditions. The announcement named no buyer or sale price.

Rare-disease peer Mirum Pharmaceuticals, Inc. NASDAQMIRM announced on Sept. 25 that the FDA approved Atebrioz for patients aged 12 and older with fibrodysplasia ossificans progressiva. Mirum expects U.S. availability in October. The same release says the associated priority review voucher went to its licensor, Incyte Corporation NASDAQINCY, rather than Mirum.

Read more: Mirum Pharmaceuticals wins FDA approval for Atebrioz in FOP patients 12 and older

The iShares Biotechnology ETF NASDAQIBB closed at US$209.77 at 4 p.m. EDT on Sept. 25. That preceded Egetis's approval and the first Stockholm session in which it could be traded.

Read more: Pharming Group says FDA accepts lower-dose Joenja sNDA for review

Egetis's next dated event is its investor call at 8 a.m. CEST on Sept. 29 to discuss the approval. Management's launch timetable will face its first test when Emcitate becomes commercially available, which the company estimates at eight to 10 weeks after the Sept. 28 approval.