Overview
Receipt of a CRL slows approval, causing increased costs and lost sales, and may prompt withdrawal. The FDA Amendments Act (FDAAA) provided the FDA with new powers in relation to drug safety, including the authority to impose postmarketing requirements (PMRs) and Risk
Evaluation and Mitigation Strategies (REMS) on drug manufacturers, which took effect on March 25, 2008. The FDAAA has increased the costs of drug development due to a rise in post-approval spending: the average number of PMRs issued per drug was four in 2011 compared to two in 2008. Complex REMS, which are issued relatively infrequently, require a significant investment from the applicant compared to REMS that only require medication guides and/or communication plans, and the impact on drug sales is almost certainly negative.
CONTENTS
5 EXECUTIVE SUMMARY
5 Overview of US drug approval regulations and procedures
5 Complete Response Letters and impact on approval
6 Take-home messages to avoid Complete Response Letters
8 REGULATIONS AND PROCEDURES OF RELEVANCE TO COMPLETE RESPONSE LETTERS
8 The FDA regulatory burden is increasing
13 US drug submissions process
18 References
20 COMPLETE RESPONSE LETTERS AND IMPACT ON APPROVAL
20 Trends in Complete Response Letters
29 FDA advisory committee meetings and Complete Response Letters
34 References
35 TAKE-HOME MESSAGES TO AVOID COMPLETE RESPONSE LETTERS
35 Common deficiencies that trigger a Complete Response Letter
38 Case studies
39 Neutroval (tbo-filgrastim)
40 Bydureon (exenatide)
41 Nucynta ER (tapentadol)
42 Lamictal (lamotrigine)
43 Menveo (meningococcal ACWY vaccine)
44 Horizant (gabapentin enacarbil)
46 APPENDIX
46 About the author
46 Scope
46 Methodology
LIST OF FIGURES
8 Figure 1: Full-time equivalent FDA staff, FY2000–10
10 Figure 2: Number of postmarketing requirements by drug approval year, 2000–11
20 Figure 3: Approvals, Complete Response Letters, and withdrawals as a percentage of total applications, FY2009–12
22 Figure 4: Approval delay (months) for submissions that received a single Complete Response Letter
30 Figure 5: Number and percentage of NME/BLA submissions referred to advisory committee, FY2008–11
32 Figure 6: Comparison of advisory committee votes and approval status
36 Figure 7: Common deficiencies that trigger a Complete Response Letter
LIST OF TABLES
9 Table 1: Number of NDAs/BLAs and FDA workload, FY2009–11
11 Table 2: Number of postmarketing requirements by drug approval year, 2000–11
21 Table 3: Number of drug submissions, Complete Response Letters, resubmissions, and approvals, FY2009–12
25 Table 4: Company comments and action taken after receiving a Complete Response Letter