MethylGene Reports Encouraging Preliminary Clinical Results for MGCD0103 in Ongoing Hematologic Oncology Trial.

MONTREAL -- MethylGene Inc. (TSX:MYG) a biopharmaceutical company, today announced preliminary and interim results regarding MGCD0103, its oral isotypic-selective HDAC inhibitor for cancer, in an abstract published during the American Society of Hematology's (ASH) 47th Annual Meeting in Atlanta (December 10-13th, 2005; Abstract # 4639). In conjunction with this abstract, the Company also released additional preliminary and interim clinical data for seven patients with refractory acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS) treated with MGCD0103 at doses of 60-80mg/m2. Four of these patients have had reductions in bone marrow blasts, with treatment still ongoing in three patients. Pharmacodynamic and pharmacokinetic results further support these data.

"At the current dose level of our oral agent, MGCD0103, we are seeing single-agent anti-leukemia activity," commented Dr. Robert E. Martell, Vice President and Chief Medical Officer for MethylGene. "These data are preliminary with more data to be gathered to classify these patients as responders according to formal criteria. However, we are encouraged by these early results and believe that they may help define a patient population that could benefit from treatment with MGCD0103."

"We have seen preliminary evidence of activity in four patients with refractory leukemia or MDS in this trial, including patients treated at doses that appear to be well tolerated," noted Dr. Guillermo Garcia-Manero, M.D., Principal Investigator and Associate Professor of Medicine, Leukemia Department, University of Texas MD Anderson Cancer Center.

Rationale: MGCD0103 is a novel isotypic-selective inhibitor of the histone deacetylase (HDAC) enzyme. There are 11 functionally differentisoforms of HDAC with some involved in cancer while others are not.It is hypothesized that specifically inhibiting those HDACs involved in cancer with MGCD0103 may restore normal cell function and reduce or inhibit tumour growth with fewer side effects than non-selective HDAC inhibitors.

Method: MGCD0103 is administered orally three times per week in patients with blood cancers such as advanced myelodysplastic syndrome (MDS), acute myelogenous leukemia (AML) and acute lymphocytic leukemia (ALL).

Results: The Company reported preliminary and interim data on the first 15 patients with highly resistant AML or MDS. Four of seven patients treated at the two highest dose levels (60 and 80 mg/m2), after receiving one or two cycles of MGCD0103, have had reductions in bone marrow blasts with treatment ongoing in three of these patients. In this trial, four dose levels have been evaluated with MGCD0103. Dose limiting toxicities were gastrointestinal in nature at 80mg/m2. Patients are now being treated with 60mg/m2, a dose which appears to be well tolerated, provides pharmacodynamic activity on the target and exhibits anti-leukemia activity. As previously reported, the half-life of MGCD0103 was determined to be 9 hours and pharmacodynamic data revealed prolonged HDAC inhibition at 72 hours in some patients. Analysis of HDAC activity in peripheral white blood cells indicates that HDAC inhibition occurs in a dose-dependent manner.

Status: Patient enrollment continues at 60mg/m2.

Dr. Garcia-Manero will describe preliminary results on two of the patients where bone marrow reductions were observed in a session entitled, "Managing Myelodysplasia in 2005" at the Corporate Friday Symposium being held in Atlanta on Friday December 9, 2005 just prior to the ASH Conference.

Additional Phase I/II MGCD0103 Hematologic Oncology Trials Ongoing

MethylGene initiated a second hematology trial in October 2005 administering MGCD0103 twice per week in MDS, AML, and ALL patient populations. MethylGene is also exploring combination Phase I/II trials using MGCD0103 with other chemotherapeutics such as azacitidine (Vidaza(TM)), a demethylating agent, and other undisclosed agents.

About MethylGene

MethylGene is a publicly-traded biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics in cancer and infectious disease. Two cancer product candidates are currently in clinical trials: MGCD0103, partnered with Taiho Pharmaceutical for certain Asian countries, and MG98, partnered with MGI Pharma for North America.

MGCD0103 is currently in Phase I dose-escalation monotherapy trials against solid tumours and hematological malignancies and also in a Phase I/II combination trial with azacitidine. MG98 has entered a randomized two-step Phase II combination trial with interferon alpha in metastatic renal cell cancer. MethylGene has an exclusive license agreement with Merck & Co. for the development and commercialization of small molecule beta-lactamase inhibitors to overcome antibiotic resistance. MethylGene has a portfolio of preclinical programs for its multi-targeted kinase and histone deacetylase (HDAC) inhibitors for both oncology and non-oncology indications, and continues to seek partnering opportunities in these areas. Please visit MethylGene's website at www.methylgene.com.

Except for historical information, this news release may contain forward-looking statements, which reflect the Company's current expectation regarding future events. These forward-looking statements involve risk and uncertainties,(which can be found in the Company's Annual Information Form dated December 31, 2004, and can be found on www.sedar.com) which may cause but are not limited to, changing market conditions, the successful and timely completion of clinical studies, the establishment of corporate alliances, the impact of competitive products and pricing, new product development, uncertainties related to the regulatory approval process and other risks detailed from time to time in the Company's ongoing quarterly and annual reporting.

MethylGene Inc. (TSX:MYG)