Botox and Nausea Patch Combination May Help Prostate Cancer Patients

New research shows a dual-protective approach to treat dry mouth side effects.

A novel approach using Botox injections coupled with an anti-nausea patch is showing promise. This could help advanced metastatic castration-resistant prostate cancer (mCRPC) patients combat severe dry mouth, allowing them to continue radioligand therapy.

Dual Therapy Approach

A team led by Dr. Jingjing Zhang from the National University of Singapore investigated this dual approach. They found that botulinum toxin (BTX) Type A (IncoA) combined with a scopolamine patch may offer protection against salivary gland toxicity, a known side effect of prostate-specific membrane antigen (PSMA)-targeted radioligand therapy.

“This study offers a promising therapeutic strategy for reducing radiation-induced salivary gland toxicity without compromising PSMA tumor uptake,”

—Dr. Jingjing Zhang

The researchers conducted a preclinical study involving 14 patients. Each patient underwent one to two cycles of PSMA-targeted radioligand therapy, using lutetium-177 (Lu-177) and actinium-225 (Ac-225). According to the National Cancer Institute, prostate cancer is the most common cancer among men in the United States, with over 288,000 new cases estimated in 2023 (Source 2023).

Study Details

Before treatment, patients received 16 BTX injections, with ultrasound guidance, in their parotid and submandibular glands. Some patients had BTX alone, while others also used the scopolamine patch behind their ears three days before treatment. Pre-therapy PSMA PET/CT scans confirmed tumor and salivary gland uptake. Post-therapy SPECT/CT was used for restaging.

The team found a significant reduction in PSMA uptake in BTX-treated parotid and submandibular glands. Post-injection SPECT/CT images also confirmed a marked reduction in PSMA radioligand uptake. Patients without scopolamine showed no major difference in uptake.

While injection-related hematoma occurred in one patient, and some experienced scopolamine-induced dry mouth, no patient discontinued PSMA therapy. Dr. Zhang added that this could “expand the therapeutic utility of PSMA radiopharmaceutical therapy, particularly with alpha-emitting radionuclides like 225Ac.”

Further studies are needed, but this combined approach may improve the quality of life for those undergoing PSMA radioligand therapy.