The concept of an antibody drug conjugate, or ADC, is straightforward: a cancer-killing drug is chemically linked to an antibody that targets the delivery of the therapy to a tumor. This drug class has made progress with several approved products and many more on their heels in clinical development. But there’s still plenty of room to improve on this type of targeted cancer therapy, contends Dominik Schumacher, CEO of Tubulis.
When an ADC releases its drug payload too early, it hits healthy tissue and sparks toxic effects, Schumacher said. Also, current ADC designs are restricted in their ability to match the biology of cancer targets. Tubulis has a pipeline of ADCs designed with technologies intended to overcome those limitations. The startup is moving closer to the clinic and this week it announced the closing of €128 million (about $139 million) to support its research.
There is no single linker or drug payload that makes sense for all ADCs, Schumacher told MedCity News in a January interview following the J.P. Morgan Health Care Conference. Tubulis’s technologies give the startup multiple ways to add things to an antibody using linkers that improve an ADC’s stability—a stable ADC is less likely to release its drug payload prematurely. The technologies also enable the company to develop ADCs with more potent drug payloads.
“We believe that our platform is one of the most flexible ones in the industry,” Schumacher said.
Tubulis has two lead programs, both in preclinical development but perhaps not for long. TUB-030 is an ADC that targets 5T4, a protein expressed by many solid tumors. The second lead program, TUB-040, targets Napi2b, a protein found in ovarian and lung cancers. Tubulis says it has optimized both ADCs for long-lasting and durable tumor engagement as well as minimal off-target toxicity. Preclinical proof-of-concept data for both are set to be presented in April during the annual meeting of the American Association for Cancer Research in San Diego. The company also said it expects to start its first Phase 1/2a clinical trial this year.
Tubulis’s technologies are based on research from the Leibniz Research Institute in Berlin and the Ludwig Maximilians University in Munich. These technologies have already caught the eye of Bristol Myers Squibb, which last year paid $22.75 million to gain access to the German company’s ADC payloads and its ADC conjugation platform. BMS will use the Tubulis linker technology to develop more stable ADCs. Schumacher said BMS’s research will be guided by Tubulis’s support and expertise. He added that while Tubulis is open to additional partnerships, such deals are not a core part of the startup’s business, which remains focused on developing its internal drug pipeline.
Tubulis last raised money in 2022, a Series B round that was announced as €60 million. Tubulis describes its new round as a Series B2 financing, adding in an email that it is not an extension of the Series B round. However, the new €128 million financing includes the undrawn last tranche of the prior Series B round. In total, the company says it has raised €187.1 million, which includes non-dilutive funding received in 2019.
In addition to supporting ongoing development of the Tubulis pipeline, the new capital will also fund a new a U.S. subsidiary. Potential sites are still being evaluated. The latest round of investment was co-led by EQT Life Sciences and Nextech Invest. New investors that joined the round are Frazier Life Sciences and Deep Track Capital. All earlier investors also participated, including Andera Partners, BioMedPartners, Fund+, Bayern Kapital (with ScaleUp-Fonds Bayern), Evotec, Coparion, Seventure Partners, Occident, and High-Tech Gründerfonds.
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