AstraZeneca and Daiichi Sankyo have reported updated data from the Phase I TROPION-PanTumor01 clinical trial, where their datopotamab deruxtecan (Dato-DXd) showed to offer encouraging responses in heavily pretreated metastatic triple-negative breast cancer (TNBC) patients.

The two-part, open-label, multicentre trial is designed to evaluate the safety and initial efficacy of datopotamab deruxtecan in advanced solid tumour patients. 

These subjects are relapsed or are refractory to standard therapy, or have tumours for which standard treatment is currently unavailable. 

Dose-limiting toxicities and serious adverse events comprise the safety endpoints of the trial. 

Duration of response (DoR), objective response rate (ORR), time to response, progression-free survival (PFS), and overall survival (OS) are the trial’s efficacy endpoints. 

According to the findings, datopotamab deruxtecan showed to offer an ORR of 32% in the TNBC cohort of the trial.

Additionally, the median PFS and OS were reported to be 4.4 and 13.5 months, respectively, in the overall cohort.

Datopotamab deruxtecan’s safety profile was in line with priorly reported findings, without any new safety signals reported.

The companies also reported data from an open-label, two-part, multicentre Phase Ib/II BEGONIA trial analysing Imfinzi plus cancer therapies, with or without paclitaxel, as a first-line treatment for metastatic TNBC. 

This trial’s Arm 7 is assessing the safety, tolerability, and initial efficacy of datopotamab deruxtecan plus Imfinzi in priorly untreated, unresectable, locally advanced, or metastatic TNBC patients.

As per the data, the combination therapy offered an ORR of 73.6%.

Additionally, the safety profile of datopotamab deruxtecan plus Imfinzi was in line with those already reported for each agent. 

AstraZeneca and Daiichi Sankyo are jointly developing datopotamab deruxtecan, an investigational TROP2-directed antibody-drug conjugate.

AstraZeneca chief medical officer and oncology chief development officer Cristian Massacesi said: “The median duration of response of nearly 17 months seen in the TROPION-PanTumor01 trial in these patients reinforces the potential of datopotamab deruxtecan to treat this persistent disease. 

“These results, along with the promising clinical response in combination with Imfinzi seen in the BEGONIA trial, underscore the potential role of this TROP2-directed antibody-drug conjugate for patients with triple-negative breast cancer, as both a monotherapy and in combinations.”

In December last year, the companies reported that Enhertu (trastuzumab deruxtecan) offered a greater PFS and ORR in the Phase III DESTINY-Breast03 trial for breast cancer.