Look out, Teva. Neurocrine's Ingrezza wins Huntington's disease FDA nod to rival Austedo

With a new FDA approval to rival Teva's Austedo, Neurocrine Biosciences’ Ingrezza is debuting in a treatment area with hundreds of millions of dollars of revenue potential.

Late last week, the FDA approved Ingrezza capsules to treat adults with chorea associated with Huntington’s disease. Ingrezza was first approved in tardive dyskinesia in 2017. With its second approval, the medication’s label now largely stacks up to Teva Pharmaceutical Industries' rival vesicular monoamine transporter 2 inhibitor Austedo, which picked up its own Huntington’s disease chorea nod in 2017.

Despite lagging Austedo with its chorea nod, Ingrezza “maintains multiple competitive advantages” over its entrenched rival, analysts at William Blair wrote in a note to clients this week.

Namely, the medication is dosed just once a day and features “simple” titration, the William Blair team said.

The specified titration period to the recommended dose on the chorea label for Ingrezza is about five weeks, which includes a starting dose of 40 mg increased every two weeks by 20 mg to reach 80 mg. This “compares favorably” to Austedo, the analysts said, which was previously administered twice a day and requires a more incremental dose escalation over five to seven weeks.

In February, Teva scored approval for Austedo XR, a once-daily formulation of its drug.

The William Blair team figures there are about 30,000 Huntington’s disease patients in the U.S., “the vast majority of whom will show chorea symptoms.” Removing some 20% of patients who could be contraindicated due to depression and suicidality (noted in a classwide black box warning on Ingrezza), the team estimates a total addressable patient population of 23,000. With potential uptake of about 30%, the William Blair team estimates Ingrezza could clinch revenues of at least $500 million in 2030 in Huntington’s disease chorea alone.

Chorea is an abnormal involuntary movement disorder associated with Huntington’s disease, itself a hereditary progressive neurodegenerative disorder in which the loss of certain neurons in the brain cause motor, cognitive and psychiatric symptoms. Chorea can affect various body parts and interfere with motor coordination, gait, swallowing and speech, Neurocrine said in a press release.

Not all analysts are as hopeful about Ingrezza’s sales prospects in this condition. Focusing in on the black box warning for suicidal ideation and depression, which was “likely unexpected for the company,” analysts at Mizuho Securities pegged 2030 Huntington’s sales for Ingrezza at just $205 million. The Mizuho team figures Ingrezza will bring down roughly $2.7 billion in tardive dyskinesia sales that same year.

“We believe the company's internal sales expectation for the HD indication could be lower because of this [black box] warning,” the Mizuho team said.

The FDA based its Ingrezza approval on data from two clinical trials, KINECT-HD and the open-label extension trial KINECT-HD2.

In the late-stage KINECT-HD study, Ingrezza met its primary endpoint of reduction in the Unified Huntington’s Disease Rating Scale total maximal chorea score from baseline at Weeks 10 and 12. Treatment with Ingrezza led to average improvement of 3.2 points versus placebo on the 28-point scale, representing a “notable reduction in chorea severity,” the William Blair analysts said.

Ingrezza has already breached the blockbuster barrier. Last year, the med brought home $1.43 billion in sales for Neurocrine. In February, Neurocrine said it expected to generate Ingrezza sales between $1.67 billion and $1.77 billion in 2023. The company raised that range to $1.77 billion to $1.82 billion in August.

Austedo, for its part, hit $936 million in North American revenues in 2022. In May, Teva’s CEO Richard Francis suggested the drug could clinch sales of $2.5 billion by 2027.

"We are going all in on Austedo," he said during a recent investor day. As part of that Austedo initiative, Teva is planning to ramp up its investment on the drug, including by bringing on a bigger sales force, Reuters previously reported.