WILMINGTON — Clinical trials at Prelude Therapeutics have made significant headway with Phase 1 results of one of its drug candidates showing promising results.
Interim data of clinical studies for a drug candidate known as PRT3789, a first-in-class, highly selective degrader of SMARCA2 protein was “well-tolerated” through eight doses levels – ranging between 24 milligrams to 376 milligrams. The drug was administered through intravenous dose to 65 patients with tumors, with more than half the patients diagnosed with non-small cell lung cancer. Prelude representatives show that most of the side effects of the treatment were mild to moderate.
Of the 26 patients with advanced non-small cell lung cancer or esophageal cancer, four saw partial responses to PRT3789, including two non-small cell lung cancer patients that were treated at higher doses.
Additional patients in the study were found to have a stable disease, meaning there were no visible changes in the tumor which could mean there is no improvement or progression. One of those patients in the client has been stable and in the clinical study for treatment for more than a year.
The clinical trial results have been long awaited, as Prelude had made seeing clinical proof for PRT3789 a top priority this year. PRT3789 is one of many small molecule drugs the company is developing to target the SMARCA2 protein, which along with SMARCA4 controls gene regulation through chromatin remodeling. As SMARCA4 deficient cancer cells become dependent on SMARCA2, Prelude is focusing its efforts to target the protein to treat the disease.
Prelude has reported that up to 70,000 cancer patients in the United States and European Union who currently have limited treatment options could benefit from drugs like PRT3789.
“The highly selective degradation of SMARCA2 can make meaningful differences for patients whose tumors harbor a SMARCA4 mutation. We are continuing our dose escalation to arrive at an optimal biological dose to advance into larger backfill cohorts of a homogeneous population of patients,” Prelude Therapeutics CEO Kris Vaddi told investors in September.
Prelude first presented the preliminary data to investors in early September, and later shared results at the EORTC-NCI-AACR Molecular Targets and Cancer Therapeutics Symposium in Barcelona. There, representatives also shared that study results were also showing that PRT3789 was enhancing the effectiveness of select chemotherapy treatments, as well as quality of care with patients with non-small cell lung cancer.
The study also showed that PRT3789 resulted in the complete degradation of the SMARCA2 protein both as a single treatment or taken with chemotherapy drug docetaxel with no adverse side effects.
Now headed in the final months of 2024, Prelude will end the year with increased doses of PRT3789 by the end of the year. The drug developer has started Phase 2 trial, where PRT3789 will be tested in combination with Keytruda, through a deal signed earlier this year with Merck.
The news comes as Prelude Therapeutics reports it still holds $153.6 million in cash, cash equivalent and securities as of Sept. 30. That is enough financial runway until 2026. By the third quarter of 2024, the company reported spending $29.5 million on research and development, a slight increase from $26.3 million the previous quarter. However, research and development costs may vary, depending on the timing of clinical development.
Prelude has a robust drug candidate portfolio and has started enrolling the first patients in a multi-dose trial for PRT7732 to treat SMARCA4 mutated cancers. The company has also entered into an agreement with Pfizer Ignite to provide access to “Pfizer’s significant resources, scale and expertise in developing potentially breakthrough medicines.”
