Chinese Clinical Trials of PSMA-targeted RLT Drug for Metastatic Prostate Cancer Are Approved

Release Date:2022-12-29
Author:先通医药

On December 28, 2022, the clinical trial application for [177Lu]Lu-XT033 injection, a class I new drug developed by Sinotau, was approved, which means [177Lu]Lu-XT033 is one step closer to commercialization and clinical application.

The project has already initiated ethical filing and other preparations, and will advance to clinical enrollment as soon as possible.

[177Lu]Lu-XT033 injection, which is another milestone in the innovative development of radionuclide therapeutic drugs in China, will benefit patients with metastatic prostate cancer and is a new option and hope in the field of precision therapy for metastatic prostate cancer.

About [177Lu]Lu-XT033 injection
[177Lu]Lu-XT033 injection is a radioligand therapy (RLT) drug intended for the treatment of adult patients with metastatic prostate cancer whose prostate specific membrane antigen (PSMA) is positive. RLT was introduced in the 1940s and works by combining a targeting compound (ligand) with a therapeutic radioisotope (radioactive particle). When injected into the bloodstream, the radioligand binds to the tumor so that the radiation produced is more locally focused on the tumor tissue, reducing damage to other healthy tissues of peripheral and whole body. The radioisotope, which acts as therapeutic agent, can disrupt tumor cell replication or trigger tumor cell death. Compared with traditional radiotherapy for tumors, RLT therapy has the advantages of precise targeting, powerful killing and limited damage, and plays a crucial role in the treatment of tumors in clinical practice.

PSMA is an ideal target for prostate cancer precision therapy. The world’s first PSMA-targeted prostate cancer RLT drug, 177Lu-PSMA-617 (trade: Pluvicto) developed by Novartis, was approved for marketing in the U.S. on March 23, 2022. In 2018, Novartis acquired Endocyte for $2.1 billion and acquired this product. Results from a subsequent global phase III clinical trial showed that 177Lu-PSMA-617 significantly improved overall survival (OS) and radiologic progression-free survival (rPFS) in patients with PSMA-positive mCRPC and reduced the risk of death for patients by 38% compared to the best standard of care.

177Lu-labeled PSMA-targeted RLT drugs can specifically bind prostate-specific membrane antigen (PSMA) to achieve enrichment of the active ingredient at the prostate tumor site and kill tumor cells using beta-rays emitted by [177Lu] lutetium decay, causing DNA damage, disrupting the replication ability of tumor cells and/or triggering cell death, thus achieving precise treatment of metastatic prostate cancer adult patients. [177Lu]Lu-XT033 injection innovates on the basis of 177Lu-PSMA-617 by introducing an albumin affinity group-Evans blue (EB), with a view to achieving increased drug uptake in the target tumor and enhancing its anti-tumor activity.

Prostate cancer is the second most common cancer in men, and the fifth most common cause of cancer death in men. In recent years, the incidence of prostate cancer in China has been on a significant rise, with an incidence rate of 9.92/100,000, which means that there are nearly 9.8 prostate cancer patients among 100,000 people. Although the incidence of prostate cancer in China is lower than that in Western countries, the proportion of patients with advanced stages at diagnosis is higher than that in Western countries.