PTC Therapeutics 2026 Q2 Earnings Call

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

I'm 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 today. I'm excited to share the results of another quarter of outstanding execution across the company. Starting with revenue, we achieved another record quarter with total revenue of $361 million, including $239 million of product revenue, driven by continued strong global tafiam sales. Based on this performance, we are raising our full year 2026 product revenue guidance to $850 million-$950 million and now expect total revenue of $1.18 billion-$1.28 billion. In addition, with our continued effective management of expenses, we remain in position to potentially reach the milestone of being cash flow breakeven in 2026. I'll begin with an update on tafiam's global launch. Momentum remains strong in the quarter, with continued steady growth in the U.S. and accelerating growth internationally.

Second quarter global Sephience revenue was $151 million, up 21% quarter-over-quarter, with the majority coming from the U.S. and increasing contributions internationally. As of June 30, we had 1,647 commercial patients on Sephience globally. We continue to see broad uptake across all patient segments and age groups worldwide. There remains strong underlying demand for Sephience, and our teams continue to effectively execute. In the U.S., we now have received prescriptions from 100% of the centers of excellence, as well as prescriptions from other centers not previously designated as centers of excellence. This breadth of penetration this early in the launch is impressive, we will now work to continue to penetrate deeper into these centers. We continue to see demand across disease severities and treatment histories, including treatment-naive patients, prior therapy failures, and those switching from existing treatments.

Adherence rates remain strong, we continue to hear reports not only of meaningful reductions in phenylalanine and increasing evidence of diet liberalization, but also of Sephience's benefits on mood, cognition, and quality of life. These dynamics of strong demand and reported patient benefit reinforce our confidence in Sephience's long-term commercial opportunity. In international markets, momentum for Sephience continues to build. Commercial sales in Japan began to ramp in Q2 following our first commercial sale in late March. We started expanded access programs in a number of European countries and have seen positive progress towards future revenue in Latin America, including Brazil, where Sephience recently received the highest classification for therapeutic benefit from the country's Drug Market Regulation Chamber. As we have previously shared, we expect international revenue to increasingly contribute in late 2026 and into 2027 as additional markets come on board.

Based on the continued strong launch momentum and the persistent strong underlying demand, we remain confident in the $2 billion-plus global commercial opportunity for Sephience. Turning to the votoplam Huntington's disease program, in April, we reported positive top-line results from the 24-month interim analysis of the PIVOT-HD long-term extension study. At month 24, votoplam demonstrated dose-dependent slowing of disease progression on cUHDRS, including an average slowing of 52% relative to natural history in the 10 milligrams stage 2 cohort. We continue to observe a favorable safety profile across doses and disease stages. These data support the potential for votoplam to provide long-term, meaningful clinical benefit for individuals affected by Huntington's disease. We also shared that Novartis has initiated enrollment in the global phase III INVEST-HD study, which is being conducted and funded by Novartis.

The study is expected to enroll approximately 770 individuals with early symptomatic disease, randomized 3 to 2 to receive votoplam 10 milligrams or placebo, the study includes an interim analysis. While the phase III study remains the base case for votoplam approval, The Novartis and PTC teams are finalizing a plan to engage with FDA in the second half of 2026 to discuss the 24-month results and potential accelerated paths. For the vatiquinone ataxia program, based on discussions with FDA, we have finalized a study protocol for the open-label trial with a natural history comparator arm to support NDA resubmission. We plan to initiate this study, PROVE FA, in the third quarter of this year. The trial will enroll approximately 120 individuals ages 7 to 21, the study primary endpoint is the change in mFARS from baseline to month 24.

The study design reflects the key learnings from our prior development work and has understandably generated enthusiasm within the FA community, particularly because it offers patients the opportunity to access therapy without the uncertainty of receiving a placebo. We believe the study design, coupled with our experience in FA therapy clinical development, meaningfully enhances the probability of success of the PROVE FA study and the potential to deliver an important new therapy for children and adults affected by FA. Shifting to our other clinical pipeline programs, we have initiated the phase I study of PTC612, our oral NLRP3 inhibitor, and have completed several of the single and multiple ascending-dose treatment cohorts. Notably, this healthy volunteer study will enroll a cohort of individuals with obesity and cardiovascular disease, which we expect will provide an early view of PK/PD effect.

As we have previously shared, PTC612 is differentiated from other NLRP3 inhibitors in terms of potency, selectivity, and chemical structure. Later in the third quarter of this year, we expect to initiate a phase II-A study of PTC844, our next-generation DHODH inhibitor. PTC844 is highly selective for the DHODH enzyme and benchmarks favorably to other DHODH inhibitors in preclinical potency models. The PTC844 study will be a 12-week PK/PD study in which we will assess treatment effect on biomarkers related to T-cell and B-cell immunity. The results of this study will help inform the ultimate target indications for PTC844. We have also made a number of advances in our splicing platform. We recently selected a development candidate for our MSH3 splicing program, PTC303. MSH3 is increasingly recognized as an important target for triplet repeat expansion diseases, including Huntington's disease and myotonic dystrophy.

As we have discussed, targeting MSH3 provides a complementary approach to HCT lowering in addressing the key pathological causes of Huntington's disease. The MSH3 program also further reinforces PTC's leadership in the discovery and development of oral small molecule splicing therapies. We expect it to be in the clinic in 2027. Overall, the company remains in a very strong financial position. In June, we strategically managed the 2026 convertible note liability with the refinancing of the majority of the existing notes at a 0% coupon and 40% conversion premium to the stock's closing price at the time of the deal. We closed the quarter with over $2.2 billion in cash and remain in position to achieve cash flow breakeven in 2026.

I'm proud of our team's outstanding performance in the first half of 2026 as we continue to make significant progress across the business. I'll now turn the call over to Eric to provide a commercial update, including additional details on the Sephience launch.

Eric? Thanks, Matt. In the second quarter, our commercial team continued the strong global launch of Sephience, driving solid product revenue and reinforcing confidence in our growth trajectory through 2026 and beyond.