Where Will the Data Roller Coaster End?

Our data is great!

Um, sorry about that -- our data can't be trusted!

Well, actually, our data looks like the drug works at the highest dose!

That pretty much sums up Peregrine Pharmaceuticals' last few months with its cancer drug bavituximab. And I'll throw on a big "maybe" to that last assertion.

The company announced yesterday that its issue with a third-party vendor mixing up the placebo and drug vials was limited to just the 1 mg/kg dose. The higher 3 mg/kg dose, with its 13.1 months of median overall survival, should be accurate.

So, the company took the 1 mg/kg dose, combined it with the placebo group, and compared that new combined data to the 3 mg/kg, concluding that the high dose of bavituximab "continues to show favorable tumor response rates, progression-free survival and overall survival (OS) over the new combined control arm."

Note the lack of numbers. Lack of mention of statistical significance. "Peregrine expects to announce more detailed results from the analysis in the near term when it is completed," the press release read. Not sure why they didn't just wait until the data was available to let us know about the "favorable" data.

The lack of information is frustrating, although if what Peregrine is saying is correct, the data are actually better than first reported. In September, the company said the placebo group, which also received Sanofi's Taxotere, produced a 5.6 month median overall survival. The 1 mg/kg group, also including Taxotere, produced an 11.1 month median overall survival, so we can assume that the groups weren't completely mixed because otherwise they'd have the same overall survival. Assuming then that there are only some placebos in the 1 mg/kg and vice versa, we can assume the placebo actually fared worse and the 1 mg/kg fared better than first reported.

That makes the 3 mg/kg dose look even better compared to placebo, although it introduces another issue because the overall survival of the 1 mg/kg dose was already close to the 3 mg/kg dose. While certainly not required -- there are plenty of explanations why you wouldn't see one -- a dose response, where the lower dose produces an interim result between the placebo and the high dose, gives investors confidence that response seen is due to the drug and not some random issue, such as not balancing the dosage groups properly.

Peregrine appears to be planning to take bavituximab into phase 3 based on the good-then-bad-then-good data. If Peregrine does move on without repeating the phase 2 trial, we'll be left in a similar situation to the phase 3 trial for Aeterna Zentaris (NASDAQ: AEZS) and Keryx Biopharmaceuticals' (NASDAQ: KERX) cancer drug perifosine in advanced colorectal cancer where the phase 3 drug is a crap shoot. And we all know how that turned out.

Of course, optimists can cite Sequenom -- which discovered issues with the data for its Down syndrome test, ran a new trial, and now has a product on the market.

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The article Where Will the Data Roller Coaster End? originally appeared on Fool.com.

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