Lantheus Acquires Rights to Life Molecular’s RM2 Targeting GRPR for Prostate and Breast Cancers

Published on: 

GRPR, or gastrin-releasing peptide receptor, is part of the bombesin G protein-coupled receptor family and has been found to be overexpressed in multiple cancers.

Lantheus Holdings announced on June 27, 2024 that it had acquired global rights to an RM2 licensed to Life Molecular Imaging, originally developed by Bayer, that targets the gastrin-releasing peptide receptor (GRPR) (1). The acquisition includes the novel, clinical-stage radiotherapeutic and radiodiagnostic pair 177Lu-DOTA-RM2 and 68Ga-DOTA-RM2.

Life Molecular defines an RM2 as a small peptide that binds with high affinity to the GRPR (2). It is highly expressed in early and recurrent prostate and other cancers, and in the press release announcing the acquisition, Lantheus mentioned prostate and breast cancers as two types that the radiotheranostic pair would be used to target (1).

Further expanding upon that, Lantheus said 68Ga-DOTA-RM2 also targets lung, pancreatic, colorectal, gastric, and ovarian cancers, all of which along with prostate and breast cancer overexpress GRPR (1,3). The first dosimetry in humans, according to Lantheus, yielded favorable dosimetry and safety profiles, also confirming preclinical data that showed the dose-dependent efficacy of 177Lu-DOTA-RM2.

GRPR is known to help regulate gastrointestinal movement, gastric emptying, smooth muscle contraction, and trypsin release and is involved in not only immune functions but also those of the brain, including memory, circadian rhythm, and the modulation of stress, fear, and anxiety (3).

The companies on both sides of the announcement applauded the acquisition, which was made for an upfront price of $35 million, plus potential regulatory milestone payments, with royalties.


“While new PSMA [prostate-specific membrane antigen]-targeted diagnostics and therapeutics are transforming prostate cancer care, there are many patients for whom PSMA-targeted therapy may not be appropriate,” Brian Markison, Lantheus CEO, said in the press release. “Targeting GRPR with 177Lu-DOTA-RM2 and 68Ga-DOTA-RM2 creates a potential new option to expand access to radiotheranostics for more prostate cancer patients. This expands our therapeutic offerings and opens avenues for commercial synergies.”

“With Lantheus’ experience developing and providing access to radiotheranostics in cancer, we are confident in our decision to hand them the reins for this promising theranostic pair and are honored to work with them toward improving the future for people with prostate and breast cancer,” Ludger Dinkelborg, CEO of Life Molecular, said.

Lantheus said it will begin a Phase I/IIa study with 177Lu-DOTA-RM2 in prostate cancer patients in 2025, with 68Ga-DOTA-RM2 used as a companion diagnostic (1). Life Molecular will continue to collaborate with Lantheus, according to the release, to complete the Phase I/IIa dose escalation study.


1. Lantheus Holdings. Lantheus Acquires Global Rights to Life Molecular Imaging’s Novel Therapeutic and Diagnostic Pair Targeting GRPR for Prostate and Breast Cancers. Press Release. June 27, 2024.
2. Life Molecular Imaging. Life Molecular Imaging Announces Presentation of New Scientific Data at the European Association of Nuclear Medicine Annual Meeting 2022. Press Release. Oct. 14, 2022.
3. Ma, Y. and Gao, F. Advances of Radiolabeled GRPR Ligands for PET/CT Imaging of Cancers. Cancer Imaging online, Jan. 26, 2024, 24 (19).