This Day On The Street
Continue to site
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

Pfizer Presents Phase 2 Data Showing Investigational Therapy PD-0332991 Plus Letrozole Significantly Improved Progression Free Survival Compared With Letrozole Alone In Patients With ER Positive, HER2 Negative Advanced Breast Cancer

In patients with measurable disease, the objective response rate was 45 percent for those women who received PD-991 plus letrozole versus 31 percent for those who received letrozole alone. The clinical benefit rate (defined as complete response plus partial response plus stable disease for ≥24 weeks) was 70 percent versus 44 percent, respectively. The differences observed in the objective response rate and clinical benefit rate were statistically significant. The most frequently reported treatment-related Grade 3/4 adverse events (AEs) in patients who received the combination therapy were neutropenia, leucopenia, anemia and fatigue.

Both Part 1 and Part 2 of this Phase 2 evaluation are ongoing but no longer enrolling new patients. Final efficacy and safety data are expected to be presented at a future medical congress.

“In demonstrating very strong efficacy and a manageable tolerability profile, these new data represent a potential major advancement in breast cancer clinical research and our continued efforts to identify new medicines that target patients most likely to have an optimal response,” said Dr. Richard S. Finn, Associate Professor of Medicine, Revlon/UCLA Women’s Cancer Research Program at Jonsson Comprehensive Cancer Center, UCLA, and lead investigator of the Phase 2 trial. “The oncology community is looking forward to the further evaluation of PD-991 in the planned Phase 3 trial and very interested in the potential for this novel CDK 4 and 6 inhibitor to improve the treatment landscape for patients with advanced breast cancer.”

About PD-991

PD-991 is an investigational, oral and selective inhibitor of the CDK 4 and 6 kinases. CDK 4 and 6 are two closely related kinases that enable tumor cell progression during phase G1 to phase S in the cell cycle. This progression is necessary for DNA replication and cell division. Inhibition of CDK 4 and 6 has been shown to prevent the deactivation of retinoblastoma, a tumor suppressor protein, and interfere with tumor cell progression. In pre-clinical studies, PD-991 was shown to be an inhibitor of cell growth and a suppressor of DNA replication by preventing cells from entering S phase.

2 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
Real Money

More than 30 investing pros with skin in the game give you actionable insight and investment ideas.

Product Features:
  • Access to Jim Cramer's daily blog
  • Intraday commentary and news
  • Real-time trading forums
Only $49.95
14-Days Free
14-Days Free
AAPL $93.21 -0.44%
FB $117.80 -0.22%
GOOG $701.26 0.80%
TSLA $211.34 -5.00%
YHOO $36.94 2.61%


Chart of I:DJI
DOW 17,660.71 +9.45 0.05%
S&P 500 2,050.63 -0.49 -0.02%
NASDAQ 4,717.0940 -8.5450 -0.18%

Free Reports

Top Rated Stocks Top Rated Funds Top Rated ETFs