Biotech IPOs Heat Up: Sionna and Aardvark Make Moves in CF and Obesity Markets

Sionna Therapeutics Raises $191 Million in Upsized IPO

Cystic fibrosis-focused Sionna Therapeutics has made its debut on the Nasdaq, raising gross proceeds of $191 million in an upsized initial public offering. The Waltham, Massachusetts-based company priced its shares at $18, the upper end of its previously announced range, and increased the number of shares offered from 8.8 million to 10.6 million.

Sionna, trading under the ticker "SION," plans to use the funds to advance a combination therapy consisting of an NBD1 stabilizer and complementary modulator through phase 1 and phase 2a trials, with the goal of progressing into phase 2b. The company has yet to determine which specific molecules will be included in this combination.

Notably, Sionna's strategy involves potential collaboration with industry giants. The biotech intends to test its lead candidate in combination with Vertex's Trikafta, while also exploring combinations with its own CFTR modulators. Additionally, Sionna has an agreement with AbbVie that could yield up to $360 million in milestone payments and rights of first negotiation related to three CFTR modulators acquired from the pharma giant last year.

Aardvark Therapeutics Sets Sights on $103 Million IPO for Obesity Drug Development

Close on the heels of Sionna's successful listing, Aardvark Therapeutics has unveiled plans for its own initial public offering, aiming to raise up to $103 million. The obesity-focused biotech is offering 5.9 million shares priced between $16 and $18 each.

Aardvark's pipeline is spearheaded by ARD-101, a bitter taste receptor (TAS2R) pan-agonist designed to stimulate enteroendocrine cells in the digestive tract. The drug aims to release gut-peptide hormones such as GLP-1 and cholecystokinin, potentially reducing hunger through gut-brain neurologic signaling.

ARD-101 has shown promise in early studies, with phase 2 trials demonstrating appetite suppression both as a standalone treatment and in combination with established weight loss drugs from Novo Nordisk and Eli Lilly. In a study involving 20 patients with general obesity, ARD-101 resulted in a 2.51-fold greater reduction in hunger rating compared to placebo. Another study in 12 patients with Prader-Willi syndrome showed that 11 participants experienced reduced severe hunger over 28 days.

The company plans to use the IPO proceeds to further advance ARD-101's clinical development and continue work on ARD-201, a fixed-dose combination of ARD-101 and a DPP-4 inhibitor. Aardvark has already raised $129.1 million since its founding in 2021, including an $85 million Series C round led by Decheng Capital in May 2024.

As the pharmaceutical industry continues to see heightened interest in obesity and metabolic disorders, these IPOs signal ongoing investor confidence in innovative approaches to addressing significant unmet medical needs.