PREVIEW-Seattle Genetics data could make 2010 a banner year

* Leukemia trial results due late August to October

* Lymphoma results due late September to October

* Regulatory filings could come first half 2011

LOS ANGELES, Aug 19 (Reuters) - Seattle Genetics SGEN.O, a developer of antibody-based drugs, could have important data as soon as this month from a trial of its experimental leukemia treatment, followed within weeks by results from two trials of another drug for lymphoma.

Wall Street is expecting success for the lymphoma drug, but positive results for the leukemia treatment -- where the outcome is much less certain -- could really turn 2010 into a landmark year for the 13-year-old biotechnology company.

Seattle Genetics, which has a market value of about $1.2 billion and earns money from research collaborations and licensing deals, has seen its shares rise about 14 percent so far this year in anticipation of the clinical data.

They are still some 22 percent below their peak near $15 last September just before a study of a different lymphoma drug was halted when it became clear the trial would fail. So positive data this year could propel the shares further.

Analysts have low expectations for the company’s leukemia drug, but the fact Seattle Genetics has pushed back the timing of the upcoming trial results has led to some optimism patients might be living longer than expected.

The Phase IIb study is designed to show whether the drug, lintuzumab, or SGN33, in combination with low-dose chemotherapy, improves survival for people over the age of 60 who have acute myeloid leukemia (AML), the most common type of the blood cancer in adults.


Because of the severity of the disease and a lack of convincing earlier-stage data, the “prevailing consensus is that the SGN33 study will fail,” JP Morgan analyst Cory Kasimov said in a research note.

But he also said disappointing results would have a modest impact on shares, while positive findings would give the company’s stock price a significant boost.

Initial results -- to be calculated after a certain number of patient deaths -- are now expected sometime between late August and October, compared with earlier expectations for a late June conclusion.

Lintuzumab was licensed in 2005 from Protein Design Labs, now known as PDL BioPharma Inc PDLI.O, which decided not to pursue the antibody after disappointing results from AML trials using a lower dose of the drug.

Lintuzumab is an older “naked” humanized antibody that targets an antigen on myeloid leukemia cells.

The company’s lead drug candidate, brentuximab vedotin, is a conjugate made up of a tumor-targeting antibody linked to a chemotherapy drug called monomethyl auristatin E. It targets an antigen expressed on Hodgkin lymphoma (HL), several types of T-cell lymphoma and other hematologic malignancies.

Earlier trials in relapsed HL patients showed robust results and the company expects findings from a pivotal trial -- designed in concert with U.S. regulators -- as soon as late September. Results from another trial in patients with anaplastic large cell lymphoma (ALCL) are expected around the same time.

“This is a safe bet -- you don’t get paid for safe bets in this market,” said WBB Securities analyst Stephen Brozak.

Brozak has a “sell” rating on Seattle Genetics -- largely because he believes the HL opportunity for brentuximab vedotin, also called SGN35, is relatively small. There is an annual U.S. incidence of about 8,500 patients, many of whom are cured by radiation and chemotherapy.

“We believe that SGN35 is a drug that can potentially really address an unmet medical need of cancer patients with multiple types of lymphomas,” Seattle Genetics’ Chief Executive Officer Clay Siegall told Reuters in a telephone interview.

He said some 25 percent to 30 percent of HL patients end up needing more treatment so there is a strong need for options other than cytotoxic drugs with their harsh side effects.

Siegall also said the company is studying SGN35 in patients with earlier-stage lymphoma.

“Front-line therapy is ultimately where we want to go,” the CEO said.

Seattle Genetics plans to file for U.S. regulatory approval of brentuximab vedotin as a treatment for HL in the first half of 2011 and may also file for ALCL at the same time, depending on results from the upcoming trial.

“When we put out top line data, at that point we can provide more guidance on whether it is possible to submit at the same time,” Siegall said.

Leerink Swann estimates 2015 sales of brentuximab vedotin of around $302 million and lintuzumab sales of $45 million.

Seattle Genetics is developing brentuximab vedotin in partnership with Takeda Pharmaceutical Co Ltd 4502.T. Its other research collaborators include companies such as Roche Holding AG's DNA.N Genentech unit and GlaxoSmithKline Plc GSK.L. (Reporting by Deena Beasley; editing by Andre Grenon)