Nuvectis Halts Ovarian Cancer Program After Disappointing Phase 1b Results

Nuvectis Pharma has announced the discontinuation of its ovarian cancer program following underwhelming results from a phase 1b study of its drug candidate NXP800. The decision marks a significant setback for the company and highlights the challenges in developing effective treatments for this aggressive form of cancer.

Phase 1b Study Results and Program Termination

The phase 1b study, which evaluated NXP800 in patients with recurrent, platinum-resistant, ARID1a-mutated ovarian cancer, yielded disappointing efficacy data. Out of 13 evaluable patients who received the highest dose of NXP800:

• Two patients showed unconfirmed partial responses
• Three patients experienced stable disease

These results fell short of the company's expectations, leading to the decision to terminate the ovarian cancer program. Nuvectis CEO Ron Bentsur acknowledged that while the data provided evidence of NXP800's biological activity in the target patient population, the time and resources required to advance the program were deemed too significant to pursue further.

Safety Concerns and Dosing Challenges

The development of NXP800, a GCN2 kinase activator, has been fraught with challenges. Earlier in the trial, safety concerns emerged with the occurrence of grade 4 thrombocytopenia, a severe reduction in blood platelet count. To mitigate this risk, Nuvectis implemented an intermittent dosing schedule.

However, the narrow therapeutic window of NXP800 presented ongoing difficulties. Bentsur had previously noted at a H.C. Wainwright event in May that increasing the dose to potentially improve efficacy was constrained by safety and tolerability issues.

Strategic Shift and Future Plans

Following the termination of the ovarian cancer program, Nuvectis is reevaluating its development strategy for NXP800. The company plans to explore the feasibility of developing the drug candidate in other indications, leveraging the biological activity observed in the phase 1b study.

In the meantime, Nuvectis is shifting its focus to another promising candidate, NXP900, an SRC family kinase inhibitor. The company recently completed a drug-drug interaction study for NXP900, demonstrating its potential for combination with EGFR and ALK drugs. A phase 1b trial for NXP900 is slated to begin in the coming weeks, signaling a new direction for Nuvectis' clinical development efforts.

The news of the ovarian cancer program's termination had an immediate impact on Nuvectis' stock, with shares falling 18% to $6.20 in premarket trading following the announcement.