NEW YORK – After Turning Point Therapeutics' TPX-0046 demonstrated promising clinical activity in RET-altered cancers in the Phase I/II SWORD-1 clinical trial, the firm on Tuesday said it plans to expand the study into multiple Phase I dose expansion cohorts and meet with the US Food and Drug Administration.
The San Diego-based drugmaker also presented preliminary data from the Phase I/II trial involving 21 patients, 10 with non-small cell lung cancer and 11 with medullary thyroid carcinoma. Three of the NSCLC patients and two of the MTC patients had not previously received tyrosine kinase inhibitors. The remaining patients had previously received RET TKI.
As of the March 10 data cutoff, four out of five patients who were RET TKI-naïve experienced tumor regressions and three remained on treatment awaiting their next scan. Among nine TKI-pretreated patients evaluable for efficacy, three achieved tumor regressions and remained on treatment.
TPX-0046, a RET/SRC inhibitor, has so far been generally well tolerated by patients, and researchers have not yet determined the maximum tolerated dose. Based on these preliminary results, Turning Point will modify the SWORD-1 study to include a dose-expansion portion, which will involve adding clinical trial sites and enrolling up to 75 patients with RET-altered cancers.
"We look forward to advancing our development of TPX-0046 in both the RET-positive TKI-naïve and less heavily pretreated TKI-pretreated settings," Mohammad Hirmand, Turning Point's executive VP and chief medical officer, said in a statement.
The company anticipates meeting with the FDA at the end of the trial's Phase I portion, once the recommended Phase II dose has been determined.