Allegro Diagnostics, a molecular diagnostics company based in Maynard, Mass., released positive results from the AEGIS I (Airway Epithelium Gene Expression In the Diagnosis of Lung Cancer) clinical trial, which demonstrate the diagnostic accuracy of the BronchoGe genomic test in combination with bronchoscopy.
BronchoGen is Allegro Diagnostics' lead genomic test, and it is built on the company's molecular testing platform that utilizes gene expression of cytologically normal epithelial cells in the respiratory tract to aid in the diagnosis of lung cancer.
"These positive results show significantly higher sensitivity and negative predictive value in lung cancer diagnoses using BronchoGen in combination with bronchoscopy than by bronchoscopy alone," said Gerard Silvestri, M.D., professor of pulmonary and critical care medicine at the Medical University of South Carolina, and a principal investigator of the AEGIS studies. "The data suggest that BronchoGen has the ability to aid bronchoscopy in better predicting the presence or absence of cancer, possibly avoiding costly and risky invasive procedures."
The AEGIS I trial is a prospective, case-controlled, multi-center study designed to evaluate the prediction accuracy of the BronchoGen genomic test compared to and in combination with bronchoscopy. The AEGIS trials have included 25 medical centers throughout the U.S. with 730 patients enrolled in AEGIS I and over 1300 in AEGIS II. All patients are current or former smokers undergoing bronchoscopy for suspicion of lung cancer. Endpoints include the sensitivity, specificity, negative predictive value and positive predictive value of BronchoGen for identifying patients with malignancy.
Data was analyzed from a total of 330 patient samples—240 patients with confirmed cancers and 90 controls. Microarray analysis was performed to identify genes associated with lung cancer, and a prediction model was developed and validated using independent training (220 samples) and test sets (110 samples). The test was converted to a reverse transcriptase polymerase chain reaction (RT- PCR) platform to validate the genes discovered on microarrays, as well as to optimize performance for commercial testing. Characterization of the test was based on re-analyzing a subset (N=217) of the patient samples.
Allegro reported that the PCR-based test yielded a sensitivity of 77% (95% confidence interval [C.I.], 71-83%) and specificity of 73% (95% C.I., 67-79%). When combining the gene test with results from bronchoscopy it was reported the sensitivity of detecting lung cancer is 94% (95% C.I., 91-97%), compared to a sensitivity of only 74% for bronchoscopy alone. Further, the negative predictive value (NPV) of the combined test was 0.85 (95% C.I., 0.80-0.90), compared to an NPV of 0.65 (95% C.I., 0.59- 0.71) for bronchoscopy alone. This 20 percentage-point increase in NPV is expected to provide a much- needed improvement in clinical practice.
Complete results from the AEGIS I trial and clinical validation of BronchoGen are expected to be released later in 2012. Allegro is also conducting a phase II AEGIS trial. The company plans on commercializing BronchoGen for use with bronchoscopy in 2013.