Glycotope’s tomuzotuximab in epidermal growth factor receptor (EGFR) expressing solid tumours saw its Phase Transition Success Rate (PTSR) drop five points to 63%. The update occurred on 11 June on the heels of Phase Ib data reported at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting, held virtually on 4–8 June. PTSR is the probability, given as a percentage, of a drug progressing successfully from one development stage to the next.

The Berlin, Germany-based company updated Phase Ib GATTO trial’s secondary endpoint data, showing patients who received tomuzotuximab had a median progression free survival (PFS) of 1.9 months and a 3.8-month duration of response (abstract no 2522). The 50-patient, single-arm trial studied the combination of tomuzotuximab and Daiichi Sankyo ’s gatipotuzumab.

Despite the PTSR change, the data did not result in any change to the drug’s Likelihood of Approval (LoA), which remained at 7%. LoA is identified via GlobalData’s analysis using a combination of machine learning and its proprietary algorithm and is calculated by compounding the PTSR at each stage the drug is yet to progress through. Both LoA and PTSR can be calculated for a drug by considering characteristics like therapy area, indication and molecule type.

William Newton is a Healthcare Reporter for Clinical Trials Arena parent company GlobalData’s investigative journalism team. A version of this article originally appeared on the Insights module of GlobalData’s Pharmaceutical Intelligence Center. To access more articles like this, visit GlobalData.