MonumenTAL was a Phase I, first-in-human study of talquetamab, which is a GPRC-CD3, bispecific T-cell engager. All we determined in the study was the recommended Phase II dosing, which was 400 micrograms per kilo subcutaneously weekly, given after a two step-up doses of 10 micrograms per kilo, and 60 micrograms per kilo, respectively.
This trial was in a group of very heavily pretreated patients, who had a median of six prior lines of therapy...
MonumenTAL was a Phase I, first-in-human study of talquetamab, which is a GPRC-CD3, bispecific T-cell engager. All we determined in the study was the recommended Phase II dosing, which was 400 micrograms per kilo subcutaneously weekly, given after a two step-up doses of 10 micrograms per kilo, and 60 micrograms per kilo, respectively.
This trial was in a group of very heavily pretreated patients, who had a median of six prior lines of therapy. Also, note 27% of those treated at the recommended Phase II dose had had prior BCMA directed therapy. 100% of those at the recommended Phase II dose were triple-class refractory, and 80% were penta-drug refractory.
We found that the drug was well tolerated, that cytopenias were mild, and generally confined to the step-up dosing in cycle one. Neurotoxicities also mild and all grade one and grade two. We did see some skin related disorders in between 60 to 77% of the patients, and nail disorders in 21% of the patients. Those were also mild and, generally, manageable with symptomatic therapy, for example, steroids for the skin peeling on the palms and soles. We saw dysgeusia in about 60% of the patients treated at the recommended Phase II dose, again, consistent with the expression of GPRC in salivary glands and in the keratinized tissue.
Notably in terms of cytokine release, overall, it was mild. It did occur at 73% of the patients treated at the recommended Phase II dose, but it was limited to grade one and grade two in all patients except one. The median duration of the cytokine release was two days and median onset was also two days.
The response rate, as I mentioned earlier, was extremely encouraging, with a 70% overall response rate. While follow-up is short, these responses do appear to be durable and deepening over time. 81% of the responders remained on treatment after immediate follow-up of 6.3 months. We do have more mature data in the IV cohorts. Even those treated at much lower dosing, we have patients who remain on treatment at 22 plus months. So, we were really very encouraged by the efficacy, safety and tolerability of talquetamab, and the Phase II expansion study is ongoing.