This Day On The Street
Continue to site
ADVERTISEMENT
This account is pending registration confirmation. Please click on the link within the confirmation email previously sent you to complete registration.
Need a new registration confirmation email? Click here

Biotech Stock Mailbag: Astex Pharma, My Essential Twitter Follows

BOSTON ( TheStreet) -- Summer's over but the Biotech Stock Mailbag remains. Chris M. emailed Wednesday with a request about Astex Pharmaceuticals (ASTX - Get Report):

Can you wait until Friday to publish the bear thesis? Or at least until the end of trading day on Thursday?

Request granted.

Astex shares rose 25% Wednesday (and remained flat Thursday) following the release of interim results from a phase II study of SGI-110, a next-generation DNA-hypomethylating agent under development for acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) -- two forms of blood cancer that affect myeloid cells.

SGI-110 is an important element in the Astex bull thesis because Dacogen, currently approved to treat MDS (and used off label to treat AML) just went generic. SGI-110 is supposed to be an improved version of Dacogen, that if approved, would be preferred over the cheaper generic by oncologists.

Astex is conducting a phase II study of SGI-110 enrolling 200 patients with AML and MDS. On its last quarterly conference call held Aug. 1, Astex executives said results from this study would be presented at the American Society of Hematology's annual meeting in December.

But surprisingly, Astex decided on Wednesday to report interim (more like incomplete) results on 67 patients enrolled in the study with at least three months of follow up as of June:

-- Eight adult patients of 50 with relapsed/refractory AML reported a complete remission. That's a 16% complete remission rate.

-- Nine elderly patients of 17 with treatment-naive AML reported a complete remission, or a 53% complete remission rate.

A couple of sell-side analysts -- RBC Capital's Michael Yee and JMP Securities' Mike King -- urged investors to buy Astex shares on their belief that Wednesday's data showed SGI-110 to be better than Dacogen.

Yee:

Data much better than older Dacogen: As cross-trial comparison, in the phase III study for Dacogen which is approved in treatment-naive (elderly) pts in Europe, Dacogen showed a 27% CR+CRi+CRp rate versus 56% sic for SGI-110 today... So SGI-110 clearly looks much more active at this stage vs older Dacogen.

Or not.

Yee's cross-trial comparison is a stretch too far. That phase III study of Dacogen enrolled 485 AML patients (242 treated with Dacogen, 243 with cytarabine or supportive care.) Concluding that SGI-110 is better than Dacogen based on an interim look at just 17 patients is silly. That 53% SGI-110 response rate will not hold up once the cohort of elderly, treatment-naive AML patients reaches full enrollment (50 patients.)

The Dacogen study also failed to demonstrate a survival advantage over control despite higher response rates. Overall survival was the primary endpoint. Astex submitted Dacogen to the FDA as an AML therapy based on these phase III data, regardless. FDA rejected the drug. European regulators approved it.

I can also search the medical literature to find other published studies of Dacogen in AML with response rates that are as good or nearly as good as those reported for SGI-110 on Wednesday.

Here's a study of Dacogen (scientific name: decitabine) in which 102 adult patients with relapsed/refractory AML reported a 16% response rate. Fifty-two elderly, newly diagnosed AML patients reported a 40% response rate.

Here's a study of clofarabine (sold by Sanofi as Clolar) with a 46% complete response rate in 112 elderly, newly diagnosed AML patients. FDA rejected Clolar as a treatment for AML in 2009.

1 of 3

Check Out Our Best Services for Investors

Action Alerts PLUS

Portfolio Manager Jim Cramer and Director of Research Jack Mohr reveal their investment tactics while giving advanced notice before every trade.

Product Features:
  • $2.5+ million portfolio
  • Large-cap and dividend focus
  • Intraday trade alerts from Cramer
Quant Ratings

Access the tool that DOMINATES the Russell 2000 and the S&P 500.

Product Features:
  • Buy, hold, or sell recommendations for over 4,300 stocks
  • Unlimited research reports on your favorite stocks
  • A custom stock screener
Stocks Under $10

David Peltier uncovers low dollar stocks with serious upside potential that are flying under Wall Street's radar.

Product Features:
  • Model portfolio
  • Stocks trading below $10
  • Intraday trade alerts
14-Days Free
Only $9.95
14-Days Free
Dividend Stock Advisor

David Peltier identifies the best of breed dividend stocks that will pay a reliable AND significant income stream.

Product Features:
  • Diversified model portfolio of dividend stocks
  • Updates with exact steps to take - BUY, HOLD, SELL
Trifecta Stocks

Every recommendation goes through 3 layers of intense scrutiny—quantitative, fundamental and technical analysis—to maximize profit potential and minimize risk.

Product Features:
  • Model Portfolio
  • Intra Day Trade alerts
  • Access to Quant Ratings
Options Profits

Our options trading pros provide over 100 monthly option trading ideas and strategies to help you become a well-seasoned trader.

Product Features:
  • Actionable options commentary and news
  • Real-time trading community
SYM TRADE IT LAST %CHG
ASTX $0.00 0.00%
ARNA $4.19 -0.24%
CELG $116.09 -0.09%
MNKD $4.52 -2.38%
PCYC $261.25 0.66%

Markets

DOW 18,232.02 -53.72 -0.29%
S&P 500 2,126.06 -4.76 -0.22%
NASDAQ 5,089.3620 -1.4320 -0.03%

Partners Compare Online Brokers

Free Reports

Top Rated Stocks Top Rated Funds Top Rated ETFs