The funding round was led by the healthcare-focused investment firm Pontifax Venture Capital, in addition to returning investors Novo Holdings and Ysios Capital. This extension follows Adcendo’s first Series A closing in April 2021, which infused the startup with €51 million ($55.6 million).
ADC challenges in sarcoma
ADCs typically consist of a monoclonal antibody bound to a toxic drug via a chemical ‘linker.’ The antibody guides the toxic compound to a specific tumor site and releases its payload, causing less damage to healthy tissue than using the toxic drug alone.
One established ADC target is the antigen Her2; for example, the ADCs Kadcyla and Enhertu are approved for the treatment of solid tumors such as breast cancer that express high levels of Her2. However, Her2 is less common in soft tissue and bone sarcoma, so more ADC targets are needed to tackle these forms of cancer.
Adcendo’s solution is uPARAP, a protein on the cell surface that is important for carrying fragments of collagen inside cells, and that was first identified by the scientific founders of Adcendo.
“The challenge of targeting soft tissue or bone sarcoma with ADCs has so far been the lack of a suitable target that is highly expressed in multiple sarcoma subtypes,” said Michael Pehl, CEO of Adcendo, in an email. “uPARAP does not only fulfil key ADC criteria such as rapid internalization and differential expression between tumor and healthy tissue but is also highly overexpressed in the large majority of soft tissue and bone sarcoma investigated so far, providing the opportunity for clinical development as a pan sarcoma asset.”
The extension round’s proceeds will bankroll the development of Adcendo’s lead candidate uPARAP ADC through to clinical proof-of-concept in multiple types of sarcoma. The company aims to begin phase 1 testing of the candidate in the second half of 2024.
The cash will also support the preclinical development of a second candidate ADC in Adcendo’s pipeline that targets a protein called GPC-1, which is found in solid tumors including prostate and bladder cancer.The candidate is being developed in a collaboration with the Australian biotech company GlyTherix that was launched in late 2022.
Markets hungry for ADCs
Since the first ADC was approved by the U.S. Food and Drug Administration in 2000, these drugs have been capturing the imagination of investors and big pharma companies alike. Startups developing ADCs have raised big funding rounds in recent months, including Pheon Therapeutics, Mablink Bioscience and MediLink Therapeutics. And an ADC specialist, Seagen, was acquired by Pfizer last month for a huge $43 billion, one of the largest acquisitions in biopharma.
“Given recent approvals of ADCs in the solid tumor space and the progress made with ADC technologies and platforms to further improve about the tolerability and efficacy profile of ADCs, the interest of pharma and investors has been very high during the past years,” explained Pehl. “The recent acquisition of Seagen by Pfizer is certainly a reflection of that.”