Tiziana Life Sciences PLC (LON:TILS) has been allowed to expand the clinical trial of its cancer drug milciclib.
The green light follows a second interim review by the independent data monitor committee monitoring the phase IIa study.
It found the drug to be reasonably well tolerated by the 11 people taking the new medication with an "acceptable incidence of serious adverse events" reported.
Those currently receiving the new treatment have a very hard to treat form hepatocellular carcinoma (HCC), the most common type of liver cancer.
Seriously ill patients opt to continue with drug
Four patients so far have completed the full treatment cycle with two opting to continue taking the drug under a protocol for compassionate use.
A third is awaiting ethical committee approval to do the same thing.
Tiziana will now enrol an additional 20 liver cancer sufferers to the trial.
The drug developer said the latest update represented an "important milestone", allowing the company to kick-off a phase IIb assessment of milciclib in harness with sorafenib, the current front-line treatment.
Chief executive Kunwar Shailubhai added: "Results from these clinical studies strongly warrant further clinical development of milciclib for treatments of HCC and other cancers."