
 
  


SAS Programs/Outputs - Provenge, December 14, 2006


 
 
(System Info - 125400 TULL LORI 04/07/2010 09:17:39 TULL)


From: Zhen, Boguang (CBER)
 Sent: Thursday, December 14, 2006 2:39 PM
 To: 'Harmon, Matt'
 Cc: Liu, Ke; 'Yuh, Lianng'; 'Smith, Liz'; Tull Lori
 Subject: SAS programs/outputs

Attachments: 9901Cox.sas; 9902a_SURV.sas

Dear Matt,

 Thanks for your help in understanding the data structure and the SAS programs
 attached in BLA 125197. As ?promised? in the previous telecon, I have more
 questions regarding the data analysis and need your further assistance.


1. Cox model -- for Study 9901
 I conducted several additional sensitivity analyses with different set of
 covariates in Cox model. In one of the analyses, I used localization of
 disease (bone and soft tissue vs. bone only or soft tissue only), PSA (<20,
 20-<100, >=100), and Gleason score (<=6, 7, >=8) as covariates . Could you
 check the program (9901Cox.sas) to make sure that I used the right
 variables/datasets?
 [Note: would like to let you know that this is just one of the many
 sensitivity analyses -- although p-value for treatment effect from this
 particular sensitivity analysis is 0.0788, p-values from many of my other
 sensitivity analyses are below the 0.05 level]
 2. Time to objective disease progression as measured by imaging -- for
 Study 9901
 I tried to repeat your analysis in 11.4.2 Time to objective disease
 progression confirmed by imaging studies (p74 of the study report) and tried
 to generate Kaplan-Meier curves for this endpoint as suggested by our medical
 reviewers . However, I was unable to do so due to failure in identifying the
 right variables/datasets. Could you generate Kaplan-Meier curves for us and
 tell me which variables you used for this analysis?
 3. Survival analysis in Study 9902a
 When I run my program for Kaplan-Meier curves and log-rank test for the
 overall survival endpoint, I found that the median survivals, CIs, number of
 events from my analysis matched with those in the study report (11.4.2.1, page
 69 of the study report) except p-value. P-value = 0.3482 from my analysis
 while p=0.331 in the study report.
 Again, when I tried to duplicate the results in Table 13: Proportional Hazards
 Regression Models of Survival (page 72), I could not match my results with
 those in the table . However, I could duplicate the results for Cox model
 using the same variables/datasets as you recommended for Study 9901.
 Could you please check my program (9902a_SURV.sas) to see if the program is
 correct? If not, please show me how to duplicate the results.


Thanks again for your help.
 Bo

 
 