Kymera Therapeutics Unveils IPO Pitch for Protein Degradation

Kymera Therapeutics has a pipeline of preclinical drug candidates that use an experimental approach to get rid of disease-causing proteins and it’s now looking to tap the public markets to finance tests of the technology in humans.

In paperwork submitted to the Securities and Exchange Commission on Friday, Kymera set a $100 million goal for its IPO. The filing comes three weeks after the Cambridge, MA-based biotech inked a multi-year, multi-product R&D partnership with Sanofi (NYSE: [[ticker:SNY]]) that paid $150 million up front.

Kymera is developing drugs that harness protein degradation, a cell’s built-in process for recycling or disposing of old and damaged proteins. The company’s drugs are designed to tag disease-causing proteins so that the proteasome—a cell’s recycling machinery—recognizes a protein as marked for disassembly. The proprietary Kymera technology, dubbed Pegasus, enables it to design the small molecules that become its drug candidates.

Lead Kymera drug candidate KT-474 targets IRAK4, a protein that is a validated target for inflammation and cancers that has, so far, proven “undruggable.” According to the filing, Kymera plans to seek FDA permission to begin clinical testing of the compound in the first half of next year. The company plans to test the drug in hidradenitis suppurativa, a rare disease that causes small, painful lumps under the skin. Kymera says it will also test the drug in patients with atopic dermatitis.

The IRAK4 program is covered by the Sanofi partnership. According to the terms of the deal, Kymera is responsible for Phase 1 testing. Sanofi gains a worldwide license to develop compounds that target IRAK4 and one additional, undisclosed target. The deal covers use of IRAK4 for any diseases except cancer. Depending on the progress of the drugs covered by the alliance, Kymera could earn more than $2 billion in milestone payments. Vertex Pharmaceuticals (NASDAQ: [[ticker:VRTX]]) is another Kymera partner. The target of that discovery-stage program is still undisclosed, according to the filing.

Two additional protein degrading programs are being readied for clinical trials, one targeting IRAKIMiD for treating diffuse large B-cell lymphoma, and another one addressing STAT3 for liquid and solid tumors. In the second half of next year, Kymera expects to file the paperwork seeking FDA permission to begin clinical testing for both programs.

Targeted protein degradation is still an experimental technology but it’s a rapidly crowding field. Arvinas Therapeutics (NASDAQ: [[ticker:ARVN]]), which has research alliances with Bayer, Roche, and Pfizer (NYSE: [[ticker:PFE]]), has already entered clinical testing. Nurix Therapeutics (NASDAQ: [[ticker:NRIX]]), which went public last week, has partnerships with Gilead Sciences (NASDAQ: [[ticker:GILD]]) and Sanofi. Other companies developing protein degrading drugs include Cedilla Therapeutics and C4 Therapeutics.

Kymera is led by CEO Nello Mainolfi, the company’s co-founder. Mainolfi was an entrepreneur-in-residence at Atlas Venture, the biotech’s founding investor. Other backers include Amgen Ventures, Bain Capital, and Bessemer Venture Partners. The prospectus shows Kymera has raised $204.5 million in financing, most recently a $102 million Series C round in March. Cash from the company’s partnerships push the company’s total haul to more than $400 million to date, the company says. Kymera’s largest shareholder by far is Atlas with a 27.6 percent stake, according to the filing. Vertex Pharma, which made a $70 million equity investment as part of the biotech’s Series B financing, holds a 7.3 percent stake.

Kymera’s cash holdings were $156 million as of June 30, the filing shows. The company says it will use the IPO proceeds to take the IRAK4, IRAKIMiD, and STAT 3 programs through Phase 1 testing. Any remaining cash will go toward the Pegasus technology and preclinical research for earlier-stage compounds in the company’s pipeline.

Friday’s IPO filing follows a confidential draft registration statement submitted to the SEC in late June. If Kymera completes the stock offering, it expects to trade on the Nasdaq exchange. The company has not yet applied for a Nasdaq listing nor has it proposed a stock symbol.

Image: iStock/RTimages