This week's Ask Dr. Durie comes from a gentleman who heard about a new treatment for myeloma in the news. The name of this treatment is talquetamab, quite a mouthful, and it is important to know what is this treatment? The first good news is that it does have a trade name, TALVEY, which may end up being the word that we use to describe this treatment.
It is a new first in class monoclonal antibody, which is a therapy for heavily pretreated multiple myeloma, and it was approved by the FDA on August 9th, 2023. Talquetamab, TALVEY, is unique and it’s a targeting of a new receptor on the surface of myeloma called GPRC5G, G protein coupled receptor with a type called class five and member D, And so this is a unique receptor, actually an orphan receptor, and we don't really know what it does under normal circumstances.
And so the new bispecific, TALVEY targets this new GPR5CD and also CD3 on the T lymphocytes. And so it brings the T lymphocytes together with the myeloma using this GPRC5D target. This is something unique and has really been quite exciting to see it move forward in clinical trials. The new receptor is heavily expressed on myeloma.
It is also expressed on hair and skin and on the tongue. And so it does have some unique side effects or toxicities where it can affect the skin and hair. And it affects taste, giving it abnormal taste. And we have a new word for the myeloma lexicon, which is dysgeusia where it indicates abnormal taste. So, the FDA approval was based upon a study called the MonumenTAL-1 trial, which used two doses, once a week and every two weeks at a 0.5 and a 0.8 dose level.
There was an initial step up dosing at the beginning of the treatment with the different scheduling and the overall response rate was really very, very good with an overall response rate of over 70% and the median PFS or response time was nine months or better. So really very excellent evidence of benefit in this heavily pretreated group of patients. Toxicities besides the unique ones included cytokine release syndrome called CRS, and also neurotoxicity, which is called ICANS. In addition to reduction and reduction in blood counts such as white blood cells and platelets, which does occur with most of these aggressive new therapies.
And so this is really a great development for myeloma patients. It will be made available to patients through a special REMS program, a risk management program, because of the unique toxicities.
And so the bottom line for this gentleman is good to pick up on this news about talquetamab. This is really an important new therapy which will really, I think, establish a new place in the myeloma armamentarium.
Something really good to have as a back up therapy and probably maybe playing a more central role over time.