NEW YORK (GenomeWeb) – Vermillion has completed a clinical utility study that indicates its OVA1 test is effective at driving patients at elevated risk of ovarian cancer to use a gynecological oncologist for adnexal mass surgery.
In the study, which was published last week in Current Medical Research and Opinion, researchers affiliated with the company found that of 122 patients with OVA1 results indicating elevated ovarian cancer risk, 109, or 89 percent, were either referred to a gynecologic oncologist for surgery or had a gynecologic oncologist available during surgery.
This, the study authors noted, compares with estimates that typically between 33 percent and 60 percent of ovarian cancer patients are treated by gynecologic oncologists, despite National Comprehensive Cancer Network guidelines that recommend all such patients undergo surgery by a gynecologic oncologist.
OVA1 measures the levels of five proteins in the blood of patients with adnexal masses to determine the likelihood the mass is cancerous, with the goal of increasing the proportion of high-risk patients who are referred to a gynecologic oncologist for surgery. The CMRO study suggests that the test is effective in this role, as nearly 90 percent of patients deemed high-risk by the test were referred to a gynecologic oncologist.
The study used data from a chart review of patients from 22 Ob/Gyns in 14 states across the US, including three from private practice, six from group practices, six from teaching hospitals, and seven from community hospitals. Of 136 patients deemed high-risk by OVA1, 122 underwent surgery for an adnexal mass, with malignancies found in 68 (56 percent) of these patients, 65 of which were primary ovarian cancer and three of which were non-ovarian metastases to the ovaries.
Of the 65 patients with primary ovarian malignancies, 100 percent had some level of gynecologic oncologist involvement at the time of surgery, with 61 having a gynecologic oncologist perform the surgery, two receiving a referral to a gynecologic oncologist but having an Ob/Gyn perform the surgery, one having a consultation with a gynecologic oncologist prior to surgery, and one having a gynecologic oncologist available to assist during surgery.
These numbers indicate OVA1's usefulness in moving ovarian cancer patients to gynecologic oncologists for surgery. However, the study data also highlights the test's relatively low sensitivity, which has proved problematic for Vermillion's commercialization efforts. Specifically, of the 122 patients who underwent surgery for an adnexal mass, 44 percent did not have a malignancy, meaning roughly half of the patients did not need a referral to a gynecologic oncologist.
Vermillion aims to address this issue with its second-generation test Overa, which offers specificity of 69 percent and positive predictive value of 40 percent, compared to 54 percent specificity and PPV of 31 percent for OVA1 while maintaining the original test's sensitivity and negative predictive value.