A vaccine slows down advanced ovarian cancer31 Mar 2015
A cancer vaccine for advanced ovarian cancer, derived by the tumor itself, has led to a significant improvement in 3-year recurrence rate, compared to treatment with surgery alone. This was achieved in a phase 2 clinical trial.
3-year recurrence rate of 60% vs 91%
In particular, patients who received the "FANG vaccine" (Vigil) have had a 3-year recurrence rate of 60% versus 91% in the control group (who only underwent surgery). The trial of the vaccine ended early when a cohort of treated patients reached a median recurrence-free survival (RFS) of 19.3 months, surpassing the historical relapse-free survival (RFS) range of 13 to 18 months. The control group had a median RFS of 12.4 months.
On the basis of the positive data from phase 1 and 2 trials, enrollment has begun for a phase 3 trial with an accrual target of 382 patients, Jonathan Oh, MD, of Texas Oncology in Dallas, said at the Society of Gynecologic Oncology meeting in Chicago.
Encouraging results leading to phase 3 trial
"The phase 1 results show encouraging survival duration and correlation of induced activated T-cell response with survival," said Oh, a gynecological oncologist. "Results in the phase 2 ovarian cancer trial suggest Vigil-mediated prolongation of time to recurrence." The oncologist continued on saying "On the basis of these findings, we think that further randomized assessment of Vigil is justified."
Medical details of the vaccine and the phase 2 trial
The oncologist reported data from a 31-patient randomized trial of patients with platinum-resistant recurrent ovarian cancer and reviewed combined clinical experience with the patient-specific vaccine made from tumor specimens. Production involves transfection of tumor cells obtained from a patient with granulocyte macrophage colony-stimulating factor and a proprietary RNA construct against furin.
The resulting immunotherapeutic product, known generically as FANG, is shipped to the patient's treating center and administered monthly by intradermal injection.
Patients in the ovarian cancer trial underwent cytoreductive surgery, and those who achieved a clinical complete remission (MRD) were randomized 2:1 to FANG or no additional therapy. The primary endpoint was recurrence-free survival (RFS).
When the trial ended, the 20 patients treated with FANG had yet to reach a median progression-free survival, whereas the control group had a median time to progression of 14.5 months. The oncologist pointed out that about 75% of patients with stage 3/4 ovarian cancer relapse within 2 years after achieving clinical complete remission with surgery.
Vaccine well tolerated by patients
Thus far, the vaccine has been well tolerated. Of a total of 50 patients treated in phase 1 and 2 trials combined, no grade 3 or 4 adverse events have occurred, and the only grade 2 adverse event was a single case of erythema.
The most frequently reported grade 1 adverse events were induration (28 patients), erythema (23), and injection-site reactions (14).
Source: MedPage Today