Astria’s navenibart (STAR-0215) granted orphan drug status for HAE
FDA designation will give 7 years market exclusivity to therapy if approved
The U.S. Food and Drug Administration (FDA) has granted orphan drug status to navenibart — the new generic name of Astria Therapeutics’ experimental therapy STAR-0215 — as a treatment for hereditary angioedema (HAE).
Orphan drug status is meant to encourage the development of therapies for rare diseases, or those affecting fewer than 200,000 people in the U.S. Among its benefits are seven years of market exclusivity if the treatment is ultimately approved, as well as exemption from FDA fees.
“Receiving orphan drug designation for navenibart is an important affirmation of our belief that there is a significant unmet need for people living with HAE,” Jill C. Milne, PhD, CEO of Astria, said in a company press release.
“We … think that navenibart could change the way that people live with their HAE,” Milne added.
In an August company newsletter, Astria announced that several bodies, including the World Health Organization and the American Medical Association, adopted navenibart as the approved generic name for STAR-0215.
The antibody-based therapy is designed to lower the levels of bradykinin, a molecule that’s produced excessively in people with HAE and is believed to act as the driver of the swelling attacks that mark the condition. Navenibart works by blocking the activity of kallikrein, the enzyme that mediates bradykinin’s production.
Orphan drug status follows last year’s FDA fast track designation
Navenibart is administered via a subcutaneous, or under-the-skin, injection, similar to Takeda’s approved HAE therapy Takhzyro (lanadelumab). However, contrary to Takhzyro which is given every other week or once monthly, navenibart is intended to be administered every three to six months.
In an ongoing Phase 1b/2 clinical trial called ALPHA-STAR (NCT05695248), the company is testing distinct dosing regimens of navenibart in adults with HAE types 1 or 2.
The trial’s participants were divided into three groups. Those in the first group received a single 450 mg injection of navenibart, while patients in the second group received one 600 mg injection of the therapy, followed by a 300 mg injection three months later. Individuals in the third group received two 600 mg injections one month apart.
Interim results showed that the rate of swelling attacks was reduced by 90% to 96% across the three dosing regimens tested. No serious side effects related to the therapy were reported.
Participants who complete ALPHA-STAR have the option to continue treatment in an extension study, ALPHA-SOLAR (NCT06007677). In that long-term study, navenibart injections will given every three months at a dose of 300 mg, or every six months at a 600 mg dose. Preliminary results are expected in mid-2025.
We believe navenibart has the potential to be the market-leading HAE treatment because of its trusted mechanism and modality, efficacy observed to date, and low treatment burden with infrequent dosing.
The company also is planning to launch a Phase 3 trial early next year to further evaluate the safety and efficacy of navenibart.
“We believe navenibart has the potential to be the market-leading HAE treatment because of its trusted mechanism and modality, efficacy observed to date, and low treatment burden with infrequent dosing,” Milne said. “We expect to share additional results from the ALPHA-STAR trial [in the fourth quarter of this year] and to progress navenibart into a Phase 3 trial initiating in the first quarter of 2025.”
Navenibart has previously received fast track designation from the FDA for the treatment of HAE. This designation is also meant to support and accelerate the development and regulatory review of therapies for serious or life-threatening conditions that have the potential to address unmet needs.
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