Noah Rosenberg
Analyst · America, we have Greg Harrison. Please go ahead
Thank you, Eric, and good afternoon, everyone. We continue to be encouraged by our engagement with the nephrology community, as we work towards the goal of developing sparsentan in a new treatment standard for FSGS and IgA nephropathy if approved. As Eric referenced earlier, there is a clear recognition that FSGS is a leading cause of end-stage kidney disease and subsequent kidney failure. Unfortunately, the incidents and prevalence of FSGS is believed to be on the rise. And there are no approved medicines indicated for this disorder. As a result, patients living with FSGS often require aggressive treatment options, such as, immune suppressive therapy, dialysis and/or transplantation. Even if these treatments are successful, they come with challenges for people to go about daily living. This significant unmet need provides us with a sense of urgency each day, as we continue to advance our program. Following the announcement of the interim results from the ongoing pivotal DUPLEX Study of sparsentan in FSGS, our medical team has continued to receive broad support, from the nephrology and advocacy communities. As we previously mentioned, sustained proteinuria reduction is recognized as a primary treatment goal amongst nephrologists in managing FSGS. This is driven by the well-accepted link among the nephrology community that lowering proteinuria results in improved kidney outcomes in this population. We are at the forefront of development with the first pivotal study demonstrating a meaningful reduction proteinuria, compared to currently available treatments. If approved, we believe, that sparsentan can become an important new treatment option that physicians can use as the base of their treatment paradigm. As Eric outlined earlier, we are in the process of discussing our plans to pursue accelerated approval submissions for FSGS with regulators. And we continue to expect, that we'll be in a position to provide an update, on our regulatory pathway, before the end of the first half of the year as planned. While we reached an important milestone with the DUPLEX Study, achieving its interim proteinuria endpoint we still need to complete the confirmatory phase of the study. Our blinded DUPLEX team continues to engage sites and investigators to ensure patient retention and maintain high-quality trial conduct, throughout the two-year eGFR endpoint of the study. I am very pleased with the progress of the study thus far. And we remain on track for top-line data from the confirmatory endpoint, in the first half of 2023. Following the interim results from DUPLEX, enthusiasm amongst key opinion leaders continues, for the upcoming readout of the Phase 3 PROTECT Study of sparsentan in IgA nephropathy. Much like FSGS, IgA nephropathy is also a leading cause of end-stage kidney disease. Notably, it is estimated to affect between 250,000 and 350,000 people in the U.S. and Europe combined. Similar to FSGS, inflammation, fibrosis and proteinuria play key roles in IgA nephropathy. Sparsentan, simultaneously and selectively, blocks the endothelin and angiotensin receptors, the areas believed to be responsible for the inflammation fibrosis and proteinuria in IgA nephropathy. Importantly, pre-clinical models of sparsentan have consistently shown the ability to prevent glomerular sclerosis and mesangial cell proliferation and reduced proteinuria in IgA nephropathy. And the importance of proteinuria as a treatment target, and its correlation to eGFR, continues to strengthen in IgA nephropathy as well. In IgAN, it has been well-established that the higher proteinuria one has a baseline, this generally translates to a fast progression of disease. And that reducing proteinuria is associated with improved outcomes. In recent publication, from Dr. Inker, in Tufts University, amongst others, further strengthen the link between early reductions in proteinuria and effects on eGFR slope in IgA nephropathy. The analysis evaluated 12 studies of multiple interventions and found the treatment effects on proteinuria, accurately predicted treatment effects on eGFR slope. Specifically, the publication cited that an observed treatment effect of approximately 30% reduction in proteinuria would confirm at least 90% probability for treatment benefit in slope of eGFR at two years. These findings are consistent with the design of our PROTECT Study. PROTECT is also similar in many ways to the DUPLEX Study but there are some notable differences between the two. PROTECT enrolls patients with one gram per gram or more of proteinuria per day, compared to DUPLEX which included those with 1.5 or more. While one gram per gram in IgA nephropathy is progressive in nature, these values are reflective of the fact that FSGS tends to be a more heavily proteinuric disease. All patients are coming into the PROTECT Study on max dose ACE/ARB therapy and there is no wash up for required randomization. And finally, as the interim analysis in DUPLEX, we measured FPRE which is a combined endpoint that requires the patients to meet both a threshold of greater than 40% reduction of proteinuria from baseline and to get below 1.5 gram per gram of proteinuria per day. PROTECT is designed with an interim assessment of relative percent reduction of proteinuria after 36 weeks of treatment. The study is powered to show, a 30% relative reduction in proteinuria for sparsentan versus irbesartan. A treatment effect of 30% will be expected to confer benefit on eGFR, compared to irbesartan over two years, consistent with the comprehensive publications from trial-level analyses in IgA nephropathy to-date. Of note, we are on track to report top-line data from the interim proteinuria analysis in the third quarter this year. Enrollment in PROTECT remains strong. We recently closed screening in the study. And anticipate randomizing the last patient in the near-future. Elsewhere in the pipeline, we have successfully completed the integration of the pegtibatinase program for HCU. As Eric outlined earlier, this is the newly assigned nonproprietary name for our TVT-058 molecule that we acquired late last year. Our optimism, to potentially develop and deliver the first potential disease-modifying therapy for HCU continues to grow, as we spend more time with the program. We have been fortunate to engage directly with the HCU community and investigators. And we look forward to integrating their insights to optimize the program, as we move forward. The Phase 1/2 dose escalation study to assess the safety tolerability, pharmacokinetic, pharmacodynamics and clinical effects of pegtibatinase, continues to advance. We have worked through some COVID-related challenges with the pegtibatinase program such as opening new sites, but we now have one site to enrollment of the final patient in the highest cohort that is currently planned. Assuming we remain on schedule, we will expect this to provide us with an initial look at, how dosing and safety are progressing in the study later this year. This should provide us with the ability to determine, if we have identified the optimal dose cohort or if the program could benefit from an additional cohort. In parallel, we continue to enhance the ongoing natural history study. We expect this to be instrumental in gaining a deeper understanding of the progression of HCU and to establishing the regulatory pathway, for the clinical program. We anticipate beginning our dialogue with regulators for HCU later this year and look forward to providing additional insights as they become available. Overall, I continue to be very pleased with our clinical efforts and our progress in pursuing our mission of identifying, developing and delivering life changing therapies to people with rare disease. I’ll now turn the call over to Peter for the commercial update. Peter.