Aptevo Therapeutics Inc. (NASDAQ: APVO) and Niowave Inc. announced a strategic collaboration to develop up to three radiopharmaceutical oncology programs. The 50/50 partnership combines Aptevo's multispecific antibody platforms with Niowave's radioisotope production capabilities.

Niowave made an equity investment in Aptevo at closing, acquiring an initial 7.9% ownership position. The investment structure includes warrants that could allow Niowave to increase its stake to 19.99% through future purchases at a premium to the initial price.

Under the agreement, Aptevo will contribute assets from its ADAPTIR and ADAPTIR-FLEX platforms, starting with targeting assets directed against Nectin-4, a protein expressed on cancer cell surfaces. Niowave will provide radioisotopes including Actinium-225 and related manufacturing capabilities.

"We have established a strong foundation and clinical proof-of-concept with our multispecific assets, and this partnership enables us to extend that capability into radiopharmaceuticals," said Jeff Lamothe, Aptevo's president and chief executive officer.

Mike Zamiara, Niowave's chief executive officer, stated the collaboration "will deepen our radiopharmaceutical development capabilities and better position us to support current partners and the broader industry."

Radiopharmaceutical therapies deliver targeted radiation directly to tumor cells. Alpha-emitting isotopes such as Actinium-225 release high-energy particles over short distances, potentially destroying cancer cells while limiting damage to healthy tissue.

The collaboration marks Aptevo's entry into radiopharmaceutical development and represents Niowave's first investment in a therapeutic development program. Development in this sector has faced constraints from limited access to critical isotopes and manufacturing infrastructure.

Aptevo is a clinical-stage biotechnology company with two clinical candidates and six preclinical candidates targeting solid tumors. Niowave, founded in 2005 and based in Lansing, Michigan, produces medical isotopes using superconducting electron linear accelerators.