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Preliminary positive results from the clinical trial of our leading product candidate are not necessarily predictive of the final results of the trial, and positive results from preclinical studies of our product candidates are not necessarily predictive of the results of our planned clinical trials of our product candidates.
As of November 2015, eight patients have been dosed and biopsied in our Phase I/IIa clinical trial for TT-034 and in the three biopsied patients for whom we have reported results we have observed shRNA expressions in the patients’ liver cells. The preliminary results from this trial are not necessarily predictive of the final results of the trial. The biological effect reported for the first three patients is not statistically significant and might not be observed in any other patients treated with TT-034. It is also important to note that in these first two dose cohorts, the biological response was designed to be, and was observed to be, lower than the level required to achieve a therapeutic effect in those patients.
In addition, positive results in preclinical proof-of-concept and animal studies of our product candidates may not result in positive results in clinical trials in humans. Many companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in clinical trials after achieving positive results in preclinical development or early stage clinical trials, and we cannot be certain that we will not face similar setbacks. These setbacks have been caused by, among other things, preclinical findings made while clinical trials were underway or safety or efficacy observations made in clinical trials, including adverse events. Moreover, preclinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that believed their product candidates performed satisfactorily in preclinical studies and clinical trials nonetheless failed to obtain FDA or other regulatory authority approval. If we fail to produce positive results in our clinical trials of our product candidates, the development timeline and regulatory approval and commercialization prospects for our product candidates, and, correspondingly, our business and financial prospects, would be negatively impacted.