Investors in ContraVir Pharmaceuticals Inc (NASDAQ:CTRV) should be smiling from ear to ear today after the company announced positive interim data from the ongoing Phase IIa headto-head study of CMX157 vs. tenofovir disoproxil fumarate, known as TDF or Viread, commercialized by Gilead Sciences, Inc. (NASDAQ:GILD).

ContraVir shares are reacted to the news, jumping nearly 18% to $1.32 in Thursday’s trading session.

Patients successfully completed both 5 mg and 10 mg cohorts, and interim data reported below are from 10 HBV-infected patients who completed 14 days of once-a-day oral dosing of 25 mg of CMX157, and two HBV patients treated for 14 days of oral dosing with 300 mg TDF.  The CMX157 treated patients showed an average 99% reduction in HBV viral load compared to baseline.  Significantly, the observed antiviral activity for CMX157 is comparable to that observed in TDF-treated patients, but at 1/12th the dose (25 mg CMX157 vs. standard 300 mg TDF).

A key goal of this study was to monitor levels of active tenofovir in the blood, exposure to which is a key predictor of off-target side effects. Following oral dosing, levels of CMX157 and active tenofovir in the bloodstream are approximately dose proportional and similar both in chronic HBV patients as well as in an earlier healthy volunteer study.  Notably, CMX157 does not appear to break down readily into active tenofovir in the blood (tenofovir: Cmax = 2.8 ng/mL; AUC = 34 ng*h/mL) in contrast to patients taking Viread® (tenofovir: Cmax 340 ng/mL, AUC 1910 ng*h/mL). The high levels of circulating tenofovir in subjects taking Viread® are consistent with results from earlier published clinical studies of Viread® in HIV and HBV patients.  These results are significant considering that CMX157 achieved similar antiviral activity compared to Viread® while significantly reducing systemic tenofovir exposure.

“We are pleased and excited with these clinical results, as they demonstrate CMX157’s great potential in our ongoing effort to develop a cure for HBV,” said James Sapirstein, CEO of ContraVir.  “The significant viral load reduction and favorable safety at this low dose of CMX157 speaks to the unique liver-targeting mechanism of our drug, which concentrates the antiviral activity of tenofovir in the liver, enabling anti-HBV efficacy at lower doses and minimal drug exposure to other tissues.  We believe, based on the data that are being generated, that CMX157 has great potential as a safe and highly potent backbone of combination therapy against HBV.” (Original Source)

On the ratings front, Maxim analyst Jason Kolbert reiterated a Buy rating on CTRV, with a price target of $4, in a report issued on September 12. The current price target implies an upside of 196% from current levels. According to TipRanks.com, Kolbert has a yearly average return of -15.9%, a 28% success rate, and is ranked #4079 out of 4182 analysts.

ContraVir Pharmaceuticals, Inc. is a development stage biopharmaceutical company which is focused primarily on the development of drugs to treat herpes zoster or shingles. The company currently developing a compound called FV-100 for the treatment of shingles. It is also developing CMX157, a potent analog of the successful antiviral drug tenofovir DF.