US MCT8 deficiency patients get 1st drug as Emcitate debuts

Sweden's Egetis Therapeutics has launched the first-ever treatment for people living with the ultra-rare genetic disease MCT8 deficiency in the US, Emcitate, with a list price of around $950,000 per year.

Emcitate (tiratricol), a thyroid hormone receptor agonist, was cleared by the FDA in September to treat peripheral thyrotoxicosis in adult and paediatric patients with MCT8 deficiency, a devastating disease that leads to impaired neurological function and chronic stress on the heart and metabolism.

The main symptoms are an inability to walk or sit independently, absent or severely limited speech, intellectual disability, feeding difficulties, and chronic stress on the heart and metabolism that result in a life expectancy of around 35 years.

Egetis' chief executive, Nicklas Westerholm, said the Swedish company had been able to launch Emcitate earlier than it had originally predicted, in an important development for "people living with MCT8 deficiency, their families, and everyone who has worked toward bringing an approved treatment to this community."

MCT8 deficiency, also known as Allan-Herndon-Dudley syndrome, is an X-linked disorder caused by pathogenic mutations in the SLC16A2 gene that impair the MCT8 transporter system that ushers thyroid hormones into the central nervous system.

As a result, the active thyroid hormone T3 can't enter the brain and builds up in the periphery to toxic levels. Emcitate addresses this by bypassing the broken cellular transporter to directly regulate thyroid hormone activity, reducing T3 levels in the periphery, although it cannot address the neurological consequences of the disorder.

"Following FDA approval, our focus is now on building on this momentum and helping eligible patients access treatment as quickly as possible," said Westerholm.

To that end, the company is setting up a patient support programme called Egetis RareLink, in partnership with PANTHERx Rare Pharmacy, to help patients and carers access the treatment.

Analysts think the product – which is Egetis' first – has the potential to reach between $300 million and $500 million a year in sales, based on an eligible patient population of 5,000 to 10,000 in the US and Europe. It has also been approved in the EU, where it has been launched in Germany at a list price of around €10,000 per month before discounts, after pricing negotiations.

The company was also awarded a Rare Paediatric Disease Priority Review Voucher (PRV) by the FDA for Emcitate's approval – which can be sold on to another company, with recent deals valued at between $150 million and $220 million – and has said it hopes to find a buyer before the end of the year.