Rare genetic disease therapy becomes world’s most expensive drug at $4.25mn

A new gene therapy to treat a very rare genetic disease that attacks the central nervous system of young children will be priced at $4.25mn in the US, making it the most expensive drug in history.

Orchard Therapeutics’ Lenmeldy this week became the first US approved medicine for metachromatic leukodystrophy (MLD), a fatal genetic disorder affecting an average of 40 new-born babies a year in the US.

The most severe form of MLD causes children in late infancy to lose all motor function and deteriorate to a vegetative state, eventually requiring round-the-clock intensive care. It is fatal for the majority of patients five years after the onset of symptoms.

Orchard, a UK-based biotech that was recently bought by Japanese pharmaceutical group Kyowa Kirin, argued that the lack of other treatments for MLD justified the price. But the decision reignites debate about the pricing of cell and gene therapies, which offer revolutionary new treatments and sometimes cures for patients with very few other options.

Among the most expensive approved gene therapies are uniQure’s haemophilia B treatment Hemgenix, at $3.5mn and Bluebird’s thalassaemia drug Zynteglo, which is priced at $2.8mn.

Bobby Gaspar, co-founder and chief executive of Orchard, said Lenmeldy was “a paradigm-shifting medicine”, adding that the company was “committed to enabling broad, expedient and sustainable access to this important therapy for eligible patients with early-onset MLD in the US”.

Orchard’s MLD treatment was given list prices of up to $3.9mn when it was approved across Europe in 2020 under the brand name Libmeldy, but national health systems negotiated steep discounts. In Germany, it was priced at €2.4mn.

Orchard cited a review by the Institute for Clinical and Economic Review (ICER), a US non-profit that attempts to calculate a fair price for drugs, which concluded last year that Lenmeldy would be cost-effective if priced between $2.3mn and $3.9mn.

Gaspar told the Financial Times that Orchard had “always taken on board” ICER’s evaluation but had decided to price the drug higher. “That’s our list price, we’ll enter into discussion with payors, there will be confidential discounts,” he said.

Without Lenmeldy, “these children will all die either in the first or second decade of life and that’s it”, Gaspar added. “Up until this medicine, there was nothing available for these kids, no way to stop that relentless decline.”

In the nine months to the end of September, the drug generated $12.7mn in revenues, Orchard said at third-quarter results last November.

“MLD places an enormous emotional and economic burden on families and caregivers — who face substantial wage loss and added expenses each year as the disease progresses — all while dealing with the unquantifiable anguish of losing their child,” said Bennett Smith, Orchard’s senior vice-president and general manager of North America.

Lenmeldy works by inserting a genetically modified version of the gene that causes MLD in a patient’s blood stem cells and delivering it via an infusion. In a trial of 37 paediatric patients with early-onset MLD treated with Lenmeldy, all children were alive at age six, compared to only 58 per cent in the control group. At age five, 71 per cent of patients could walk without assistance and 85 per cent had normal language and cognition scores.