ConjuChem Inc. released mixed results from three clinical trials of DAC:Opioid and separately said it was discontinuing development of its DAC:TI compound for clotting, causing investors to sell off ConjuChem stock and lowering its share price by 64.4 percent.

Robert DuFresne, president and CEO of ConjuChem, explained in a conference call that "we had one [DAC:Opioid] trial that showed efficacy and one trial that did not show efficacy in the endpoints we were looking to achieve." The termination of DAC:TI development, he said, was "a business decision."

ConjuChem's stock (TSX:CJC) fell C$1.77 Friday to close at C98 cents.

DAC:Opioid, designed to treat moderate to severe pain, is given intravenously. Two of the trials were proof-of-concept studies, one evaluating patients undergoing total knee replacement surgery and the other examining the compound in patients suffering from post-herpetic neuralgia. The third trial was a repeat-dose study in healthy volunteers to assess the compound's immunogenicity.

Although the trials showed DAC:Opioid had a strong safety profile, the product did not meet its primary endpoint, measured by patient use of self-administered morphine in the 48 hours following surgery, against placebo in the total knee replacement trial. That trial involved 40 patients. However, results from the post-herpetic neuralgia trial showed the compound produced statistically significant measurements of efficacy vs. placebo at most time points. Thirty patients with severe pain lasting a minimum of three months participated in the trial.

"[DAC:Opioid] worked in one trial and didn't in the other," DuFresne said, which leaves ConjuChem holding a mixed bag and unsure of what's next for the compound. The company said it would "carefully evaluate all the information" and consult with clinical advisers before making a decision.

But the decision is made on DAC:TI, a locally acting thrombin inhibitor designed to prevent localized clotting. Phase I trials of the product in hemodialysis patients with arterial-venous shunts who were undergoing a procedure to mechanically remove a clot from their shunts were designed to show safety, but ConjuChem expected to take a glance at the product's effectiveness as well.

"We did a Phase I trial with not very many patients per arm," DuFresne told BioWorld Today. "It was done for safety reasons, but we did anticipate that we would look at efficacy.

"We got safety," he added, but because of the placebo rate and the small number of patients in the trial, "it was impossible to make conclusions about efficacy."

In order to show efficacy for the product, ConjuChem would face a trial of at least 300 patients, 18 months of trial time and "a great deal of expense," DuFresne said. Throw in the "efficacy risk associated with that," and the decision to end development and focus resources elsewhere firmed up.

Although ConjuChem is finished with DAC:TI, DuFresne said a collaborator is looking at it in another indication, but his feelings are the product would not move forward there, either.

"Do I think that has a high probability of coming to fruition? No," he said.

ConjuChem's Drug Affinity Complex (DAC) technology is designed to create new drugs with enhanced therapeutic properties, compared to the original. Using the technology, a DAC drug is created with similar therapeutic activity of the original but with a longer duration of activity in the body.

In the conference call, DuFresne said the company's burn rate is about C$3 million per month. By dropping development of DAC:TI, it expects to lower that figure to C$2.5 million. With a cash position in excess of C$47 million (US$29.9 million), the company has about 20 months of cash, he said.

With DAC:TI severed and DAC:Opioid under evaluation, the company's DAC:GLP-1 Phase I trial in patients with Type II diabetes is pushed to the forefront. The study is being conducted in two portions - a group of healthy volunteers and a group of Type II diabetic patients.

"The intent of the trial is to show safety of DAC:GLP-1," DuFresne said. "The other intent is to show the efficacy of the compound in Type II diabetic patients. We expect we will be releasing data on the healthy volunteer portion of this by the end of September. Within four to six weeks after that, we expect to release the Type II diabetes patient information."

The trial involves 110 individuals, evenly split between volunteers and diabetics. On a day when ConjuChem's stock suffered, the DAC:GLP-1 trial could be a positive driver.

"In terms of major near-term news, that is it," DuFresne said. "Certainly we will have human efficacy data for that compound in the next two to three months."