Septerna Raises $150 Million to Advance Pipeline of Novel GPCR-targeted Medicines

Rare Daily Staff

Septerna closed a $150 million series B financing to advance a pipeline of G-protein-coupled receptors (GPCR)-targeting medicines including lead program targeting hypoparathyroidism.

The company will also use the new funding to continue development of its portfolio of novel small molecule candidates targeting well-validated GPCRs, including advancement of its lead program targeting the parathyroid hormone 1 receptor (PTH1R) to clinical proof-of-mechanism, and preclinical advancement of its program targeting thyroid stimulating hormone receptor (TSHR) and other earlier stage assets.

GPCR represents a group of cell surface receptors. An estimated 700 approved drugs target GPCRs, representing approximately one-third of all currently approved drugs. Despite the pharmacological success of GPCRs as a drug class to date, the large majority of potential therapeutic GPCR targets remain undrugged.

New investor RA Capital Management led the financing with participation from existing investors Third Rock Ventures, Samsara BioCapital, Invus, Catalio Capital Management, BVF Partners, Casdin Capital and Logos Capital, as well as additional new investors Deep Track Capital, Goldman Sachs Asset Management, Vertex Ventures HC, Mirae Asset Financial Group, Driehaus Capital Management, Woodline Partners LP, Soleus Capital, and an additional undisclosed investor. In conjunction with the financing, Jake Simson, partner at RA Capital Management, will join Septerna’s board of directors.

Septerna is developing its PTH1R agonist program for the treatment of hypoparathyroidism, a harmful condition characterized by the deficiency of parathyroid hormone (PTH), which controls blood calcium and phosphate levels. Hypoparathyroidism results in a wide range of debilitating symptoms, including fatigue, brain fog, muscle weakness, and in severe cases can lead to seizures, heart arrhythmias, and kidney failure. Currently available treatments for hypoparathyroidism include supplements that only partially address PTH deficiency or PTH peptide replacements, which require daily injections.

Septerna is focused on developing a first-in-class, oral small molecule PTH1R agonist designed to treat all patients with hypoparathyroidism.

“This milestone marks an important transition for Septerna to a product-development company, with plans to advance our lead PTH1R program to clinical proof-of-mechanism, while building out a multi-product pipeline for a range of diseases,” said Jeffrey Finer, CEO and co-founder of Septerna.

Photo: Jeffrey Finer, CEO and co-founder of Septerna