Eli Lilly said on April 20, 2026 that it had signed a definitive agreement to acquire Kelonia Therapeutics, a Boston-based clinical-stage biotech company that develops CAR-T cell therapies made inside the patient's body. Kelonia's shareholders will receive up to $7 billion in cash. That includes $3.25 billion paid upfront, with the rest due if certain clinical, regulatory and commercial milestones are reached.
The deal is subject to regulatory approvals and other customary conditions, and Lilly expected it to close in the second half of 2026. Lilly said it would decide how to account for the transaction when it closes and would then reflect it in its financial results and guidance.
Kirkland & Ellis acted as Lilly's legal counsel. Jefferies was Kelonia's financial adviser and Goodwin Procter its legal counsel.
What Kelonia built
CAR-T therapy reprograms a patient's T-cells, a type of immune cell, so that they attack cancer. Approved CAR-T products are made ex vivo: cells are taken from each patient, engineered in a factory and infused back, usually after a course of chemotherapy to prepare the body.
Kelonia's platform, called iGPS (in vivo gene placement system), skips that process. It uses engineered particles based on lentiviruses that are designed to enter T-cells inside the body and deliver the genetic instructions there, so the patient's own body produces the CAR-T cells.
The lead program, KLN-1010, is a one-time intravenous gene therapy that generates CAR-T cells aimed at BCMA, a protein found on the surface of multiple myeloma cells. It is in a Phase 1 trial in patients with relapsed or refractory multiple myeloma. Early results were presented in the plenary session of the American Society of Hematology's 2025 annual meeting, and Lilly said they showed initial clinical validation and promising tolerability.
“We have demonstrated the ability to achieve deep multiple myeloma remissions with significantly reduced complexity and cost relative to ex vivo CAR T-cell approaches.”
Why Lilly is buying
Lilly said the deal expands its genetic medicine capabilities with a gene delivery and integration technology that could be used well beyond the first program.
"Autologous CAR-T therapies have meaningfully improved outcomes for patients with various cancers, but significant manufacturing, safety, and access barriers mean that only a fraction of eligible patients actually receive them," said Jacob Van Naarden, president of Lilly Oncology and head of corporate business development. He said Kelonia's approach could deliver responses "in a far simpler, off-the-shelf format" and called the early KLN-1010 data highly encouraging.
Kevin Friedman, Kelonia's chief executive, said the company had "demonstrated the ability to achieve deep multiple myeloma remissions with significantly reduced complexity and cost" compared with ex vivo CAR-T approaches, and that with Lilly the platform could reach cancers beyond blood cancers and other serious diseases.
The founders and the funding
Kelonia was incubated and seed-funded by the venture firm Venrock. It came out of stealth in April 2022 with a $50 million Series A in which Alta Partners, Horizons Ventures and Venrock took part, BioSpace and Gunderson Dettmer reported at the time. The company was built on research from the Massachusetts Institute of Technology lab of co-founder Michael Birnbaum and on work by scientists at France's National Centre for Scientific Research (CNRS).
At launch Friedman was Kelonia's president and chief scientific officer. In the deal announcement he credited Birnbaum and the Venrock team with starting the company. No later funding rounds have been publicly reported, so on known funding the upfront payment alone is 65 times what Kelonia raised.
Neither company disclosed Kelonia's headcount or its founding date.
Paying for an early program
KLN-1010 is still in a Phase 1 trial and is not approved anywhere. Lilly is paying $3.25 billion upfront, and the milestone payments, which could more than double the total, depend on further clinical, regulatory and commercial progress.
Lilly's bet is that making CAR-T cells inside the body could remove the need for patient-specific manufacturing and pre-treatment chemotherapy, the two steps that limit how many patients receive CAR-T today, according to the companies.
