Vyvgart Opening to gMG Patients in UK Under Early Access Program

Vyvgart (efgartigimod alfa-fcab) is being made available to eligible adults with generalized myasthenia gravis (gMG) in the U.K. under an early access to medicines scheme (EAMS), Argenx, the therapy’s developer, announced.

An EAMS is designed to enable access to potentially lifesaving medications for patients with unmet medical needs ahead of a treatment’s regulatory approval.

The U.K. Medicines and Healthcare products Regulatory Agency (MHRA), which designated Vyvgart a promising innovative medicine last year, now issued a positive scientific opinion of the therapy under an EAMS, allowing healthcare providers to prescribe it to eligible patients while U.K. regulators decide whether to approve the treatment.

Eligible patients are adults with gMG who are positive for anti-acetylcholine receptor (AChR) antibodies — the most common type of MG causing antibodies — including those who have not responded to (refractory gMG), are ineligible for, or cannot tolerate other treatments.

“Despite currently available treatments, gMG patients in the UK face a significant disease burden and many struggle to manage the debilitating symptoms of this rare autoimmune disease,” David Knechtel, U.K. manager for Argenx, said in a press release.

“We are committed to addressing this unmet need, and are thrilled that UK healthcare professionals now have a potential new option for the treatment of their eligible gMG patients,”  Knechtel added.

gMG is caused by the immune system mistakenly producing antibodies that attack proteins, like AChRs, that are necessary for nerve-muscle communication.

Delivered directly into the bloodstream, Vyvgart is designed to block the neonatal Fc receptor, which usually prevents the degradation of antibodies circulating in the bloodstream. By blocking these receptors, Vyvgart aims to increase the rate at which disease-causing antibodies are broken down, thereby lowering their levels and easing myasthenia gravis symptoms.

The Phase 3 ADAPT trial (NCT03669588) evaluated Vyvgart’s safety and efficacy in 167 adults with gMG, 129 of whom had anti-AChR antibodies. Participants were randomized to either Vyvgart or a placebo for 26 weeks (about six months) in addition to their standard treatments.

Top-line trial data showed that Vyvgart was generally well-tolerated and led to sustained reductions in symptom severity among patients with AChR antibodies, meeting ADAPT’s primary goal. Vyvgart also outperformed placebo in patients without antibodies against AChR.

These positive findings supported Vyvgart’s U.S. approval for adults with AChR antibodies, and its approval in Japan for all gMG patients with refractory disease, regardless of antibody status.

Most ADAPT participants entered the ongoing ADAPT+ open-label extension study (NCT03770403) of Vyvgart’s long-term safety and efficacy. Preliminary results, reported in April, continued to show consistent and clinically meaningful improvements in gMG symptoms with the treatment. ADAPT+ is expected to finish in mid-2023.

Vyvgart is under regulatory review in the European Union, with a decision expected later this year. Regulatory action in the U.K. is anticipated to follow the European decision, Argenx said.

“The MHRA’s positive scientific opinion supports our belief in the value [Vyvgart] can offer to people living with gMG, and marks another advancement toward our goal of serving patients around the world,” Knechtel said.

“We look forward to continued collaboration with the agency to make this innovative therapy available to UK patients as soon as possible.”