Jonathan Leff
Analyst · Wells Fargo
Thanks, Jan. Let me start with a brief introduction, as I joined the company earlier this year and may not have met many of you on the call. I've been in the pharmaceutical and biotechnology industry for over 22 years now. I started at Merck developing SINGULAIR. I continued at Amgen, where I worked on Enbrel and Prolia, and eventually lead North American Medical Affairs. I then joined Roche, overseeing the development of ACTEMRA in rheumatoid arthritis, followed by 2 smaller biotech companies as Chief Medical Officer.
Most recently, I was the Executive Vice President and Head of R&D at InterMune, where I oversaw the development of pirfenidone for idiopathic pulmonary fibrosis. I'm really pleased to be here to advance our exciting pipeline, work with the talented staff and develop a portfolio of TransCon-derived products that will improve patients' lives. Let me continue with a review of our Phase III TransCon Growth Hormone program, and then I'll briefly introduce our 2 new pipeline candidates, TransCon PTH and TransCon CNP. Our once-weekly TransCon Growth Hormone program recently entered Phase III with the initiation of the heiGHt Trial in children with growth hormone deficiency or GHD. This important milestone follows successful end of Phase II discussions with the FDA and discussions with other regulatory agencies. We're very pleased to advance TransCon Growth Hormone into this next phase, bringing it one step closer to patients. To briefly review the trial design, the heiGHt Trial is a randomized open-label, active-controlled Phase III study that is designed to enroll approximately 150 treatment-naive children with GHD. The trial will compare patients receiving once-weekly TransCon Growth Hormone to those receiving injections of a daily growth hormone therapy. We will be using Genotropin as the comparator in our study. The dose we're using in the Phase III heiGHt Trial is similar to that used in our Phase II study, where TransCon Growth Hormone demonstrated similar efficacy, safety and tolerability to daily growth hormone. The primary endpoint is the comparison between the treatment groups of height velocity after 12 months, after which patients can then enroll in a planned open-label extension study to collect long-term safety and efficacy data. As you might expect, the design of this pivotal trial closely mirrors our Phase II study in pediatric GHD. In that Phase II trial, once-weekly TransCon Growth Hormone was evaluated versus an active comparator and demonstrated comparable effects to Genotropin. The mode of action of TransCon Growth Hormone is a key point of differentiation for our product candidate. It is the only long-acting agent that delivers unmodified growth hormone, meaning the growth hormone when released can diffuse freely into the tissues and carry out the effects of endogenous growth hormone, both in the vasculature and beyond. We think this is an important component of the TransCon Growth Hormone mechanism of action. The study shows that approximately 20% of the height velocity seen with growth hormone is associated with the effect of the hormone itself rather than its downstream effects on insulin-like growth factor 1.
In the coming months, we look forward to advancing the heiGHt Trial and continuing our initiation activities. To highlight a few plans and next steps, we'll be finalizing site selection and gaining IRB approvals with the goal of opening approximately 100 sites worldwide. We'll be actively publicizing the trial to encourage physicians to refer their newly diagnosed patients to a nearby site, and we expect to dose our first patient this fall in Australia, Europe and the U.S.
At this stage, it's early to predict when enrollment in the trial will complete. As you know, the dynamics in this indication can be challenging, and we are recruiting patients who have not yet been diagnosed. As the heiGHt Trial proceeds, sites are initiated and we are -- and we start dosing patients, we'll have more visibility on the enrollment timelines, and I will update you.
Now let me review our 2 new pipeline programs, which both leverage the same technology platform used for TransCon Growth Hormone. The first of these product opportunities is TransCon PTH for hypoparathyroidism. We plan to submit an IND in the second quarter of next year. For background, hypoparathyroidism is a rare endocrine deficiency disorder and until recently, one of the few endocrine deficiencies not treated by replacements of the missing hormone. The disease affects approximately 160,000 patients worldwide, the majority of whom developed the condition following damage or accidental removal of parathyroid glands during thyroid surgery. Hypoparathyroidism is characterized by hypocalcemia due to insufficient secretion of PTH, resulting in a variety of neuromuscular, cardiovascular, ophthalmologic, dermatologic and gastrointestinal symptoms. If unmanaged, this complex disorder can increase the risk of major long-term complications and comorbidities. Conventional therapy for hypoparathyroidism includes large doses of calcium and vitamin D. However, these approaches do not treat the fundamentals of the disease and only address hypocalcemia. Natpara recently became the only approved therapy for hypoparathyroidism. While an advance for patients, it is not optimal for fully controlling the disease. Our primary challenge is that it incompletely controls urinary calcium levels due to a short half-life. Utilizing our TransCon technology platform, we have been able to develop a product candidate designed to overcome this limitation. Based on preclinical PK/PD data generated so far, TransCon PTH appears to provide continuous PTH exposure in the appropriate range, which may achieve more physiologic replacement of PTH. This may help to simultaneously normalize serum and urine calcium and bone turnover markers. At our upcoming R&D Update, we will review the data we have generated on TransCon PTH, demonstrating its long-acting dosing profile and why we believe it provides a potential PTH replacement therapy for patients who suffer from this challenging disease.
Turning to our next product candidate, we have also developed a long-acting C-Type Natriuretic Peptide or TransCon CNP, which we believe can help manage achondroplasia and associated disorders. Many of you may be familiar with achondroplasia, which is the most common type of dwarfism with 18,000 to 24,000 patients in the U.S. and Europe. Achondroplasia is a skeletal disease characterized by disproportionate short stature. Patients have an average-sized trunk and short limbs. In the absence of an effective therapy, patients can often suffer a lifetime of health challenges, including spinal stenosis, scoliosis, foramen magnum compression, sleep apnea, ear infection and obesity, to name a few. Patients often elect to undergo surgical limb lengthening to improve proportionality through a series of burdensome and painful operations. Earlier this year, daily injections of a CNP analog in development for children with achondroplasia were reported to show a 50% increase in height velocity, supporting the therapeutic pathway. In animal models, CNP administration corrects the phenotype of the mice. However, optimal dosing of the current CNP product in development may induce hypotension in humans. Again, using our TransCon platform, we have developed a long-acting CNP prodrug that could provide efficacious levels of CNP without a high Cmax, which may improve the therapeutic window compared to daily CNP injections.
We plan to file an IND for TransCon CNP towards the end of 2017. As a long-acting CNP prodrug, we believe our candidate has the potential to provide improved efficacy with a reduced risk of hypotension compared to daily CNP, presenting a strong option for the management of achondroplasia. We believe all 3 of our priority pipeline programs, TransCon Growth Hormone, TransCon PTH and TransCon CNP, fit well within our strategy. They all present compelling opportunities to address unmet patient needs and improve management of these orphan conditions. On September 30, we will conduct a deeper dive into each of our programs, including presentations by outside experts on the market need and a thorough review of our product candidates.
Now let me turn the call over to Scott for a financial update.