A three-year-old biotechnology startup believes it can solve one of the central challenges in using radiation to treat cancer and has $110 million in new funding to test its approach.
Founded in 2020, Abdera Therapeutics is developing what are known as radiopharmaceuticals, or targeted radiation drugs. They pair a radioactive isotope capable of destroying cells with a compound that can home in on specific tumor proteins, in theory sparing healthy tissue. However, striking that balance is difficult, and currently approved radiopharmaceuticals come with safety risks to the bone marrow and kidneys.
Abdera’s approach involves a type of engineered antibody it claims can pierce into tumors and bind tightly to cancer targets, while avoiding excess accumulation in the kidneys.
The $110 million in Series B funding the company announced Thursday will help it advance its lead drug candidate into clinical testing for a type of lung cancer as well as develop other radiopharmaceuticals. Abdera previously raised $32.5 million in an unannounced Series A round that closed in 2021.
“Radiopharmaceuticals hold the potential to transform the treatment of cancer, but the ability to finely tune radioisotope delivery to the tumor, while sparing healthy tissue, remains a major challenge for this class of drugs,” said Lori Lyons-Williams, Abdera’s CEO, in a statement on the fundraising.
Leading the Series B round was VenBio Partners, a biotech-focused venture capital firm that previously backed RayzeBio, another radiopharmaceutical startup. Also investing were Versant Ventures, which co-led Abdera’s Series A, and Viking Global Investors, both of which also put money into RayzeBio.
“Several investors in our syndicate had already made investments in radiopharmaceutical companies but found our approach differentiated enough to join our financing,” Lyons-Williams wrote in an email to BioPharma Dive.
“Others have been evaluating the landscape and looking for the right opportunity and we are grateful to have attracted their interest,” she added, referring to new investors Qiming Venture Partners USA and RTW Investments.
Abdera’s most advanced drug candidate is a radiopharmaceutical targeting a protein known as DLL3, which is found at high levels in small cell lung cancer and other solid tumors, but not as frequently in healthy tissue. The company plans to soon ask the Food and Drug Administration for permission to begin clinical testing, which is expected to begin next year.
DLL3 was the target of a different kind of precision medicine acquired by AbbVie via its 2016 acquisition of Stemcentrx that failed in clinical testing.
Lyons-Williams defended DLL3 as a target for Abdera’s radiopharmaceutical, describing how the previous setback was due to issues with the drug’s cell-killing toxin.
“DLL3 is an increasingly validated target in the clinic for [small cell lung cancer] and radiotherapy is highly differentiated mechanism from other therapeutic modalities,” she wrote. Small cell lung cancer is particularly aggressive, with fewer available treatment options than other, more common forms of the disease.
One hurdle in developing radiopharmaceuticals is manufacturing, as the drugs are complex combinations of a radioisotope, a targeting compound and a linking molecule. Novartis, which sells the radiopharmaceutical Pluvicto and Lutathera, has previously been forced to suspend production over quality concerns.
Lyons-Williams said Abdera has contract partners for making their antibodies and radiolabelled drug products, as well as for isotope supply.
Along with Abdera and Rayze, other startups like Aktis Oncology and Radiopharm Ventures are working to develop radiopharmaceutical drugs. Novartis continues to invest in the field, as has the German pharmaceutical company Bayer.
Amplitude Ventures, Northview Ventures, AdMare BioInnovations and AbCellera also participated in funding Abdera.