Septerna Therapeutics has secured $150 million in Series B financing to support the development of its small molecule drug candidate for the treatment of hypoparathyroidism. The funding round was led by RA Capital Management and included participation from a range of investors, including Deep Track Capital, Goldman Sachs Asset Management, and Vertex Ventures HC, among others.
Hypoparathyroidism is a rare disease characterized by insufficient amounts of parathyroid hormone, which is important for regulating calcium and phosphate levels in the blood. Current treatment options include oral calcium and vitamin D supplements, but when these are ineffective, the only FDA-approved option is a daily injection called Natpara, which has limited supply and is set to exit the market soon.
Septerna’s drug candidate is a small molecule designed to activate the parathyroid hormone 1 receptor (PTH1R), which stimulates the production of the deficient hormone. The company’s platform, called Native Complex, isolates G-protein coupled receptors (GPCRs) outside of the cellular environment, allowing for the identification of molecules that target these receptors, which have previously been considered undruggable.
CEO Jeffrey Finer stated that the company believes there is a significant opportunity for an oral small molecule PTH1R agonist for patients with hypoparathyroidism, as most other companies are focused on injectable peptides. If successful, Septerna’s drug would stand apart from the field.
The funding will be used to advance the PTH1R agonist to clinical proof-of-mechanism and support the development of the company’s other programs, including a small molecule that targets the thyroid stimulated hormone receptor (TSHR).
Septerna is not alone in its pursuit of alternative treatments for hypoparathyroidism. Other companies, such as Ascendis Pharma, Amolyt Pharma, Extend Biosciences, and MBX Biosciences, are also developing injectable drug candidates. However, Septerna’s focus on an oral small molecule drug provides a potential advantage in terms of convenience and patient preference.
The participation of crossover investors in the funding round suggests that Septerna may be considering an IPO in the future. However, CEO Jeffrey Finer stated that the company’s goal was to have a strong, well-rounded syndicate of investors, and future financing options would be considered based on what is best for Septerna, its investors, and its programs.
Overall, the funding from the Series B financing round will enable Septerna to advance its drug candidate for hypoparathyroidism and potentially provide patients with a new and safer oral treatment option. With the support of investors, the company aims to bring its drug through clinical trials and ultimately make a significant impact in the field of hypoparathyroidism treatment.
