Labopharm Receives Second Approvable Letter from FDA for Once-Daily Tramadol LAVAL, QC, May 31 - Labopharm Inc. today announced that it has received a second approvable letter from the U.S. Food and Drug Administration (FDA) for its once-daily formulation of tramadol. In the second approvable letter (dated May 30, 2007), the FDA stated that Labopharm has not demonstrated the efficacy of its once-daily formulation of tramadol because the statistical methods used to analyze data from Labopharm's clinical trials did not adequately address missing data relating to subjects who dropped out of the trials. The FDA did not provide guidance with respect to how the statistical methods were not adequate. The Company will seek to clarify the issue with the FDA at the earliest possible opportunity. "We are extremely disappointed by the FDA's assessment of our response to its initial approvable letter," said James R. Howard-Tripp, President and Chief Executive Officer, Labopharm Inc. "We believe that we adequately addressed all of the matters raised by the FDA in its first approvable letter. Our top priority remains the final approval of our once-daily tramadol in the U.S." Labopharm plans to discuss the most recent approvable letter with the FDA as soon as possible to determine the appropriate path forward to achieve final approval. Potential outcomes with respect to resolution of the issues range from utilization of current data to the need to generate additional data. Prior to the recent approvable letter, the FDA had indicated that it would not proceed with the Formal Dispute Resolution process, which was initiated by Labopharm last December, while the response to the September 28, 2006 approvable letter was under review. The Company will evaluate whether to proceed with the Formal Dispute Resolution process going forward. About Labopharm Inc. Labopharm is an emerging leader in optimizing the performance of existing small molecule drugs using its proprietary controlled-release technologies. The Company's lead product, a unique once-daily formulation of tramadol, is being commercially launched in key markets globally and it has a robust pipeline of follow-on products in both pre-clinical and clinical development. For more information, please visit www.labopharm.com. This press release contains forward-looking statements that involve a number of risks and uncertainties relating to the Company's once-daily tramadol product in the United States that could cause actual results to differ materially from those indicated in the forward looking statements. These statements reflect the Company's current expectations regarding future events. Specifically the risks and uncertainties the Company faces include but are not limited to: the Company's ability to resolve the issues identified by the FDA to the FDA's satisfaction in a timely manner; the uncertainties related to the regulatory process, including regulatory approval, and the commercialization of the drug thereafter. There can be no assurance that the Company will be able to resolve the issues identified by the FDA using existing data, or at all. If the Company is unable to resolve the issues identified by the FDA using existing data, it would need to generate additional data in order to obtain FDA approval. The Company's once-daily formulation of tramadol may not be legally marketed in the United States prior to approval by the FDA. Investors should consult the Company's ongoing quarterly filings and annual reports for additional information on risks and uncertainties relating to these forward-looking statements. The reader is cautioned not to rely on these forward-looking statements. The Company disclaims any obligation to update these forward-looking statements.