Precigen shares fall 26.5% after U.S. approval of rival treatment for recurrent respiratory papillomatosis
Key Facts
The U.S. Food and Drug Administration granted accelerated approval to Papzimeos to treat adults with recurrent respiratory papillomatosis, a rare disease that causes wart-like growths in the airway. In its announcement on October 30, the agency said the approved indication is intended to reduce the frequency of surgeries needed to remove those growths. The announcement came after the regular trading session closed, so its impact appeared in after-hours trading that day. Precigen, which sells Papzimeos to adult patients with the same disease, fell 26.5% to $5.10, according to Benzinga data. By contrast, Inovio rose 292.6% to $2.37 as investors welcomed approval of its new treatment.
The approval of Papzimeos is based on an open-label, multicenter trial involving 32 adults, according to the FDA. Among 26 patients who had undergone at least three prior surgeries, 7 required no surgical intervention during the first year after treatment. That result represents 27% of that group, the agency said. The FDA said the indication focuses on reducing the need for surgery, an outcome directly tied to the burden of recurrent disease on patients. The agency described the decision as the first U.S. approval of a plasmid DNA-based immunotherapy.
Accelerated approval carries an important regulatory condition: its continuation may depend on confirming clinical benefit in confirmatory studies, according to an FDA document. Inovio must submit a draft study protocol by December 30, 2026, followed by the final protocol by June 30, 2027. The agency requires the study to include at least 50 adult and pediatric patients. Surgical interventions must also be followed for at least 3 years after completion of treatment. These requirements set out a path to determine whether the reduction in surgeries seen in the initial trial will persist in a broader population and over a longer period.
Papzimeos enters a market where Papzimeos had held full approval to treat adults with recurrent respiratory papillomatosis since August 14, 2025. At the time of approval, the FDA had described it as the first approved treatment for the disease. Precigen's second-quarter 2026 results showed Papzimeos sales of $53.1 million, within total company revenue of $55.0 million for the quarter. The drug's sales reached $74.7 million in the first half of the year. The figures highlight the product's contribution to the company's revenue during that period, as patients and relevant parties now have another treatment for the same disease with U.S. approval.
Inovio said it expects Papzimeos to be available for ordering and shipping about 60 days after the approval announcement, and is targeting a full commercial launch in the first quarter of 2027. The company said it had engaged Syneos Health to support the recruitment and deployment of its medical and commercial teams ahead of the launch. It also scheduled an investor call for November 2, 2026, at 8:00 a.m. Eastern time to provide further details about the approval. The company said the call would cover elements of the prescribing information and its marketing plan. The availability and launch dates remain company targets, while the confirmatory study is one of the regulatory requirements following accelerated approval.
Before the decision, Inovio had said the FDA was reviewing its application for the drug INO-3107 under the accelerated approval pathway, with October 30, 2026, set as the target decision date. That date coincided with the announcement of Papzimeos' approval. Precigen, meanwhile, announced that it would report its third-quarter 2026 results and provide business updates on November 4, 2026. The company scheduled its earnings call for 4:30 p.m. Eastern time. The update will follow the announcement of new competition and the recording of quarterly Papzimeos revenue in the second quarter, as attention turns to what the company will say about its business.