Otsuka Pharmaceutical subsidiary Astex Pharmaceuticals has reported updated clinical results from the Phase III ASCERTAIN clinical trial of Inqovi in adults with intermediate and high-risk myelodysplastic syndromes (MDS), including chronic myelomonocytic leukaemia (CMML).
Inqovi is an oral fixed-dose combination of an approved anti-cancer Deoxyribonucleic acid (DNA) hypomethylating agent, decitabine, and cytidine deaminase inhibitor, cedazuridine (ASTX727 or DEC-C).
In July 2020, Inqovi obtained approval from the US Food and Drug Administration to treat adults with intermediate and high-risk MDS, including CMML.
The randomised, crossover trial assessed a once-daily dose of Inqovi tablet against a 20mg/m² intravenous (IV) dose of decitabine given daily for an hour for five days on a 28-day cycle for two cycles.
Subjects continued to receive Inqovi from the third cycle onwards, Astex noted.
The primary endpoint was a total five-day decitabine area-under-the-curve (AUC) equivalence of oral decitabine plus cedazuridine and IV decitabine.
As reported earlier, the oral/IV decitabine five-day AUC was 98.9% with a 90% confidence interval between 92.7% and 105.6%.
According to the latest findings, the trial achieved a median overall survival (mOS) of 31.7 months.
Furthermore, the safety data were in line with those expected with IV decitabine while the occurrence of cytopenias was slightly increased with Inqovi during the first cycle as against the IV decitabine.
Thrombocytopenia, neutropenia and anaemia were the most common adverse events (AEs) observed, which were consistent with anticipated AEs with a parenteral hypomethylating agent.
Following the updated efficacy results from the mature data set, 22% of subjects attained a complete response and an overall response rate of 62% was observed in the trial.
Astex Pharmaceuticals chief medical officer Harold Keer said that based on the data from the ASCERTAIN clinical programme, Inqovi is being analysed along with other agents for haematological malignancies.
Keer commented: “The first of these studies is investigating the all-oral combination of decitabine and cedazuridine with venetoclax for the treatment of AML.”
Astex reported that Phase III trials of guadecitabine (sSGI-110) failed to meet the primary endpoint of improving overall survival in leukaemia patients, in October last year.