PTC Therapeutics, Inc. 2026 Q3 Earnings Call

Please go ahead. Good afternoon, and thank you for joining us to discuss PTC Therapeutics' third quarter 2026 corporate update and financial results.

I am joined today by our Chief Executive Officer, Dr. Matthew Klein, our Chief Business Officer, Eric Pauwels, and our Chief Financial Officer, Pierre Gravier. Today's call will include forward-looking statements based on our current expectations. These statements are subject to certain risks and uncertainties, and actual results may differ materially. Please review the slide posted on our investor relations website in conjunction with the call, which contains information about our forward-looking statements and our most recent quarterly report on Form 10-Q and annual report on Form 10-K filed with the SEC, as well as our other SEC filings for a detailed description of applicable risks and uncertainties that could cause our actual performance and results to differ materially from those expressed or implied in these forward-looking statements.

Additionally, we will disclose certain non-GAAP information during this call. Information regarding our use of GAAP to non-GAAP financial measures and reconciliation of GAAP to non-GAAP are available in today's earnings release. I will now pass the call over to our CEO, Dr. Matthew Klein.

Thank you all for joining us today. I am pleased to share the results of another quarter of record product revenue and solid execution across the company. In the third quarter, we achieved total revenue of $358 million, including $276 million of product revenue, led by continued quarter-over-quarter growth of SEPHIENCE sales in the U.S. and internationally. Based on this performance, we are raising our full year 2026 product revenue guidance to $960 million-$990 million, and now expect total revenue of $1.29 billion-$1.32 billion. This updated guidance represents 64%-69% in year-over-year product revenue growth. In addition, with our continued effective expense management, we expect to achieve our goal of reaching cash flow breakeven in 2026.

Beginning with SEPHIENCE, we are now one year into the global launch, which by all measures has been a great success, and all signs point to SEPHIENCE being a blockbuster rare disease product. In the third quarter, worldwide SEPHIENCE revenue was $182 million, led by consistent growth in the U.S. and continued expansion internationally. As of September 30, we have over 2,000 active patients on SEPHIENCE worldwide. In the U.S., we continue to see strong underlying demand across all patient segments. Over the course of the third quarter, we saw uptick in branded and generic Kuvan switches with continued penetration into the therapy-naive and tried and failed patient segments. Adherence remains strong, reinforcing the meaningful benefits patients are experiencing on therapy, including diet liberalization, cognitive function, and mood improvements.

Internationally, we also had continued growth in the quarter, led by the strong launch in Japan, as well as new patients granted access through named patient programs across several regions. As we have discussed, we expect international revenue to continue to grow, with acceleration points as we achieve access and reimbursement in additional countries over the course of 2027. In the first year of launch, we built a broad commercial patient base upon which we are well-positioned to expand as we move forward into 2027 and beyond. In the U.S., there remains a large number of patients still on branded or generic Kuvan who are candidates for switching, as well as a large number of patients not on any therapy that could benefit from SEPHIENCE. Overall, the vast majority of the 17,000 patients in the U.S. have yet to try SEPHIENCE.

We see strong underlying demand across all patient segments, fueled by the differentiated profile of SEPHIENCE and the growing real-world evidence of meaningful SEPHIENCE benefits. Thus, while we are proud of all we have accomplished over the past year, we believe there is still a long way to go in the launch. Furthermore, our teams have implemented plans to address a number of the key launch learnings that will support continued success in the coming years. Internationally, we expect continued growth in 2027 as we expand into new markets in Europe, Latin America, the Middle East, Russia, and the Commonwealth of Independent States, all geographies where we have experienced teams with a track record of success. Overall, we remain confident in the $2 billion-plus peak sales opportunity for SEPHIENCE. In the third quarter, we acquired the BLA-stage Fabry disease gene therapy asset, ST-920.

ST-920 is a one-time administered AAV gene therapy that provides a humanized copy of the GLA gene, enabling the body to produce sustained physiological levels of the alpha-gal A enzyme deficient in the disease. The data collected to date demonstrate that ST-920 significantly increases alpha-gal A activity, decreases the lyso-Gb3 substrate that causes organ damage, and improves renal function and other aspects of disease. In addition, the safety profile has been demonstrated to be favorable, with no serious adverse events related to hepatotoxicity or other immune reactions. We expect to complete the rolling BLA submission for accelerated approval in Q4 2026, with the potential for approval and commercial launch in 2027. Given the size of the Fabry population, our existing commercial infrastructure and experience working in the Fabry community, as well as the differentiated profile of ST-920, we believe this is a potential meaningful global commercial opportunity.

Turning to the votoplam Huntington's disease program, due to FDA scheduling, the Type C meeting to discuss the votoplam data package and a potential path to accelerated approval is now planned for the first quarter of 2027. Enrollment continues in the phase III INVEST-HD trial votoplam, which is planned to enroll approximately 770 early symptomatic patients. The primary endpoint of the study is change in cUHDRS from baseline up to 36 months, with an interim analysis planned for efficacy and futility. Excellent progress on enrollment has been made, with sites now open across the globe. For the vatiquinone Friedreich's ataxia program, we initiated the global PROVE-FA trial in the third quarter as expected. PROVE-FA is a single-arm study with a well-matched natural history comparator arm intended to support NDA resubmission. The study design, protocol, and statistical plan have all been reviewed by FDA ahead of a trial initiation.

The study is expected to enroll approximately 120 individuals between 7 and 21 years of age, with the primary endpoint being the mFARS disease rating scale. In the third quarter, we also made good progress on our other pipeline programs. We initiated a phase IIa study of PTC844, our next-generation oral DHODH inhibitor. As we shared at our R&D day last December, PTC844 has a differentiated potency and selectivity profile that benchmarks very well against approved DHODH inhibitors. The phase IIa trial is a 12-week PK/PD study being conducted in a cohort of adults with rheumatoid arthritis, with the objective of confirming the relationship between dose, DHODH inhibition, and favorable effects on markers of B-cell and T-cell immunity. We plan to use the results of this study to help finalize which rare inflammatory disorders we will pursue for PTC844 development.

The phase I study of PTC612, our oral NLRP3 inhibitor, is progressing well. We have dosed several SAD and MAD cohorts, including a cohort with inflammation and cardiovascular disease that could provide early evidence of pharmacodynamic effect on a number of biomarkers. We believe PTC612's potency, selectivity, and the potential for improved tolerability are all key points of differentiation. We plan to focus development efforts on rare pulmonary indications where NLRP3 pathology has been closely linked to disease. Finally, we continue to advance PTC303, our splicing development candidate targeting MSH3. PTC303 is our next candidate from our oral small molecule RNA splicing platform and is an example of how we are extending the reach of that platform into new and highly innovative areas of biology. By targeting somatic expansion, PTC303 has potential applications in a number of triplet repeat expansion disorders.

As we have discussed, we plan to focus on DM1 as well as Huntington's disease, where we believe PTC303 can offer a complementary approach to HTT lowering. We remain on schedule for PTC303 to enter the clinic in 2027. In conclusion, I am proud of our team's continued strong execution as we move into the fourth quarter. I will now turn the call over to Eric for a commercial update.

Eric? Thanks, Matt. Our commercial team delivered another quarter of record product revenue, highlighted by the continued strength of the SEPHIENCE global launch.