May is the time of year when Wall Street's biotech investors are usually gearing up for the annual meeting of the

American Society of Clinical Oncology

. The ASCO meeting, as it's known, is the Super Bowl of cancer drug research and takes place this year from May 29 to June 2 in Orlando, Fla.

Unfortunately, this year's ASCO conference is short on important clinical data, making the meeting something of a non-event for investors.

I don't expect to see the broad run-up in cancer-focused biotech stock prices that we've seen in years past. Instead, investors may focus only on the few biotech companies with important data to present at ASCO 2009.

ASCO will post research abstracts online for the 2009 meeting starting at 6 p.m. EDT on Thursday.

OSI Pharmaceuticals

OSI Pharmaceuticals

( OSIP) is likely to garner most of that attention. The company will be presenting data from two phase III studies looking at the use of its drug Tarceva as front-line maintenance therapy in patients with non-small cell lung cancer (NSCLC).

Maintenance therapy in NSCLC is an emerging idea that has not yet been broadly adopted by doctors. Essentially, maintenance therapy means treating NSCLC patients who respond to a first-line therapy (let's say with

Genentech's

Avastin plus chemotherapy) with a new drug like Tarceva immediately. The idea is that maintenance therapy may prolong a patient's survival by immediately knocking down residual cancer cells before they have time to regroup and start growing again.

Today, doctors typically wait for a patient's cancer to start growing again (cancer progression) before treating with a second-line drug.

OSI Pharma's Tarceva is already a well-entrenched second-line drug in NSCLC, but the company hopes that data from two phase III studies, dubbed SATURN and ATLAS, will convince doctors to use the drug more in the maintenance setting.

Eli Lilly

(LLY) - Get Report

sells the NSCLC drug Alimta and is also seeking an expansion into the front-line maintenance setting.

Roche

Outside of NSCLC maintenance therapy, the excitement level for new data at the ASCO meeting drops off considerably.

Roche

will present the data on use of adjuvant Avastin in colon cancer, but the company has already disclosed the study's failure to produce a significant survival benefit.

Roche will also be presenting final data from the phase II study of T-DM1 in breast cancer.

ImmunoGen

(IMGN) - Get Report

is Roche partner's on T-DM1, but I don't expect much positive surprise since Roche is already running pivotal phase III studies of the drug. Expect data from the first of the phase III studies in early 2010.

Synta Pharmaceuticals

Synta Pharmaceuticals

(SNTA)

will also present results from a negative clinical trial, in this case data from its failed phase III study involving the drug elesclemol in melanoma patients.

Other companies with clinical data expected at ASCO 2009 are

Cell Therapeutics

(CTIC) - Get Report

,

Celldex Therapeutics

(CLDX) - Get Report

,

Exelixis

(EXEL) - Get Report

,

Medarex

( MEDX) and

Ziopharm Oncology

(ZIOP) - Get Report

.

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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