Long-troubled drug developer Geron ($GERN) is touting what it calls "unprecedented" early results for its lead cancer drug, sending the biotech's share price up as it moves forward with partner Johnson & Johnson ($JNJ).
In two small, Phase II studies published in The New England Journal of Medicine this week, Geron's intravenous imetelstat charted a disease-modifying effect on myelofibrosis (MF) and essential thrombocythemia (ET), two uncommon hematological malignancies.
In the 33-patient MF study, Geron's drug led to a 21% rate of complete or partial remissions, and response to the treatment was particularly high among patients with certain genetic mutations. The ET study was more striking, as all 18 patients treated with imetelstat responded to the therapy, and 16 of them notched a complete hematologic response, meaning their white blood cell counts returned to normal.
The pair of studies sent Geron's shares up about 13%, as investors grew more optimistic about imetelstat's odds of success in some ongoing and future clinical trials.
The drug, a telomerase inhibitor, has had a long and rocky path to this point, dogged by safety issues and clinical failures that have repeatedly forced Geron to pause development. But the company's fortunes changed in November when, in the span of about two weeks, the FDA finally removed a longstanding clinical hold on imetelstat and Johnson & Johnson stepped in with a licensing deal worth as much as $935 million.
Now, splitting costs 50-50, J&J and Geron are running a Phase II trial testing two doses of imetelstat in refractory MF, planning to enroll about 200 patients. The pair are planning a second Phase II trial in myelodysplastic syndrome with plans to get started by the end of the year.
And the latest positive results, albeit from small studies, have emboldened Geron's management.
"The data in the ET and MF study publications in The New England Journal of Medicine provide compelling evidence that use of a telomerase inhibitor, such as imetelstat, may result in ground-breaking changes in how we approach the future treatment of hematologic myeloid malignancies," Geron CEO John Scarlett said in a statement.