NEW YORK (TheStreet) -- Intra-Cellular Therapies(ITCI) - Get Report has a poster problem.

The poster contains a full presentation of data from a phase II study of Intra-Cellular's experimental schizophrenia drug ITI-007. Kim Vanover, the company's top scientist, presented the ITI-007 data poster in May at the American Psychiatric Association annual meeting.

Investors asking Intra-Cellular for a copy of the poster in order to conduct due diligence on ITI-007 are told they can't have it. Instead, Intra-Cellular steers investors to press releases and investor presentations that explain the results (all positive) from the phase II study.

I also asked Intra-Cellular for a copy of the ITI-007 poster but was denied. "The poster is not available at this time but the company is in the process of publishing the ITI-007 Phase II schizophrenia study in a peer-reviewed journal," said a company spokesman via email.

The ITI-007 poster was presented at an open scientific meeting, so the "We want to publish the data" excuse doesn't make sense. Biotech and drug companies share publicly presented scientific data with investors all the time, making Intra-Cellular's refusal to do the same unusual.

Intra-Cellular tells a very upbeat and promising story about ITI-007. The drug significantly reduced the symptoms of schizophrenia better than placebo, according to the phase II results Intra-Cellular provides to investors. In the same study, ITI-007 matched and on some measures even surpassed the efficacy and tolerability of risperidone, an approved antipsychotic drug widely used in the treatment of schizophrenia.

Intra-Cellular is now conducting two, large phase III studies of ITI-007 in schizophrenia. Results from the first of these studies are expected in the fall, possibly as early as September. If the studies are positive and ITI-007 is eventually approved, sales could reach into the billions of dollars, which is not unusual for successful antipsychotics.

Any investor trying to handicap the ITI-007 phase III results will rely heavily on the data from the phase II study. Having the poster describing the phase II study in detail would help, but Intra-Cellular is keeping it under wraps.

Until now. I obtained a copy of the ITI-007 phase II study poster presented at the American Psychiatric Association annual meeting in May. The good news: Intra-Cellular is telling the truth when it assures investors that almost all the data described in the poster has been communicated via the company's press releases and slide presentations.

The bad news: Almost. What Intra-Cellular isn't telling investors, but is readily apparent from the poster, is that 24 patients were excluded from the intent-to-treat analysis of the study's primary endpoint. The importance of these missing patients -- whether their inclusion might have changed the outcome of the phase II study -- is hard to determine. Their omission, however, is reason enough to be concerned Intra-Cellular may be over-stating the efficacy of ITI-007.

Either way, investors deserve to know about the 24 missing patients, so they can make up their own minds about the potential impact. The information is on the poster describing the ITI-007 phase II study results -- the poster Intra-Cellular has not provided to investors.

Sharon Mates, Intra-Cellular CEO, says investors have been informed properly about all aspects of the ITI-007 phase II study. Two company-issued press releases note the phase II study randomized 335 patients across four treatment arms and that 311 patients were included in the intent-to-treat primary analysis. This accounts for the exclusion of the 24 patients from the primary analysis.

Mates says the 24 patients were not included in the intent-to-treat primary analysis for one of two reasons: The patients did not have a valid baseline measurement of schizophrenia symptoms, or patients withdrew from the study before their schizophrenia symptoms could be measured following their first treatment.

The poster describing the ITI-007 phase II study, unavailable to investors, tells a different story which doesn't gibe with Mates' math, nor with the company's prior disclosures of the study results via press releases and investor presentations.

An example: On the poster, 84 schizophrenia patients were randomized to the 60 mg dose of ITI-007, with 76 of the patients included in the intent-to-treat "ITT" primary analysis. Eight patients from the 60 mg ITI-007 arm were excluded, presumably for the reasons explained by Mates.

But the poster says 17 patients in the 60 mg ITI-007 arm discontinued treatment: Two because of adverse events, nine patients who withdrew consent and six other patients who left the study for "other" undisclosed reasons.

The eight patients in the 60 mg ITI-007 arm of the phase II study omitted from the ITT primary analysis are not accounted for in the poster's explanation of discontinuations. The same goes for the other three arms of the study. In all, data on 24 patients are missing.

Intra-Cellular says ITI-007 achieved the primary endpoint of the schizophrenia phase II study based on an ITT analysis, but what's really described in the study poster is a modified ITT or per-protocol analysis due to the omitted patients. 

This is important information investors need to make an informed investment decision about Intra-Cellular heading into the pivotal phase III study results this fall. By withholding the poster, Intra-Cellular is keeping investors in the dark.

Adam Feuerstein writes regularly for TheStreet. In keeping with company editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback; click here to send him an email.