* Avastin shows promising trend in trial but not significant
* Scientific abstract had reported statistical significance
* Good Phase I results with new gene-targeted drug PLX4032
BERLIN, Sept 23 (Reuters) - Roche's (ROG.VX) drug Avastin missed its goal in a keenly watched melanoma study, confounding initial expectations, researchers said on Wednesday.
There was an encouraging trend suggesting patients with the notoriously difficult-to-treat cancer of the skin did better when given Avastin in addition to chemotherapy, but it was not statistically significant.
A late-breaking abstract from the ECCO-ESMO cancer congress in Berlin had earlier said the drug was the first ever in melanoma to show a meaningful improvement in overall survival, raising hopes of a breakthrough. [ID:nLL728528]
But a last-minute review of the clinical data changed the outcome and researchers said the Phase II study in fact failed to meet its primary goal of proving that Avastin extended the time melanoma patients lived without their disease progressing.
It also failed to show a statistically significant increase in overall survival.
Despite the disappointment, principal investigator Steven O'Day of the Angeles Clinic and Research Institute in California said the data collected on Avastin were "very encouraging and warrant continued investigation".
The 214-patient study found the median overall survival in the Avastin arm was 12.3 months, against 9.2 months in the control arm, but there was a 19 percent likelihood that this result happened by chance.
To prove statistical significance, clinical trials require a 5 percent or less likelihood that a finding is due to chance.
On the plus side, researchers also announced early-stage results from a Phase I trial with a different drug, called PLX4032, which produced impressive results in a sub-set of melanoma patients with a particular gene mutation.
Roche is developing the new gene-targeted drug with privately-held U.S. biotech company Plexxikon.