Moonwalk Biosciences Raises $70M Series B Led by YK Bioventures

Moonwalk Biosciences Closes $70M Series B

Moonwalk Biosciences, a biotechnology company based in South San Francisco and San Diego, has raised a $70 million Series B round. The financing was led by YK Bioventures, with participation from Gaorong Ventures, Future Ventures, Khosla Ventures, ARCH Venture Partners, Eli Lilly and Company, and Alpha Wave Ventures.

The round was announced on September 8, 2026, and brings the company's total disclosed financing to at least $127 million, following its $57 million launch financing.

What Moonwalk Does

Moonwalk is developing first-in-class, adipose-targeted RNA interference (RNAi) medicines for obesity and cardiometabolic diseases. The company's approach is built around a platform that pairs human genetics, epigenomics, and multi-omics discovery with proprietary tissue-targeting chemistry.

That targeting chemistry is exclusively licensed from Suzhou Siran Biotechnology. It is designed to deliver siRNA directly to fat tissue while minimizing effects on other tissues — an approach aimed at durable weight loss, preserved lean mass, and infrequent dosing.

Lead Program and Timeline

The company's lead candidate, MW101, is an siRNA obesity therapy. It is slated to enter first-in-human clinical studies in late 2027.

Leadership

Moonwalk is led by co-founder and CEO Alex Aravanis.

The Investor Syndicate

The Series B brings together a mix of crossover life-science investors and strategic capital:

• YK Bioventures (lead)
• Gaorong Ventures
• Future Ventures
• Khosla Ventures
• ARCH Venture Partners
• Eli Lilly and Company
• Alpha Wave Ventures

The presence of Eli Lilly and Company among the participants is notable given the company's focus on obesity and cardiometabolic disease, one of the most competitive areas in biopharma.

Why It Matters

Obesity therapeutics have become one of the largest and most contested categories in drug development. Moonwalk's differentiation rests on tissue targeting: rather than broadly distributing an RNAi payload, the company aims to concentrate delivery in adipose tissue. If the approach translates clinically, it could support less frequent dosing and better preservation of lean mass than existing approaches.

That thesis remains preclinical. MW101's first-in-human studies are not expected until late 2027, meaning the Series B capital is intended to fund the company through IND-enabling work and into the clinic.

Acquisition Context

For acquirers and strategic partners, Moonwalk represents a preclinical-to-early-clinical asset in a high-demand therapeutic area, with a differentiated delivery platform and an exclusive license covering its targeting chemistry. The involvement of a large pharmaceutical company in the round signals strategic interest in the underlying technology.

Key facts at a glance:

• Company: Moonwalk Biosciences
• Headquarters: South San Francisco and San Diego
• Round: Series B
• Amount: $70 million
• Announced: September 8, 2026
• Lead investor: YK Bioventures
• Lead program: MW101, siRNA obesity therapy
• Next milestone: First-in-human studies targeted for late 2027
• CEO: Alex Aravanis