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1

24–711

" ! COMMITTEE PRINT 109TH CONGRESS

2d Session

S. PRT.

2006

109–45

COMMITTEE STAFF REPORT TO

THE CHAIRMAN AND RANKING MEMBER

REVIEW OF THE FDA’S APPROVAL PROCESS FOR

THE VAGUS NERVE STIMULATION THERAPY

SYSTEM FOR TREATMENT-RESISTANT DEPRESSION

PREPARED BY THE STAFF OF THE

COMMITTEE ON FINANCE

UNITED STATES SENATE

CHARLES E. GRASSLEY, Chairman

MAX BAUCUS, Ranking Member

FEBRUARY 2006

Printed for the use of the Committee on Finance

COMMITTEE ON FINANCE

CHARLES E. GRASSLEY, Iowa, Chairman

ORRIN G. HATCH, Utah

TRENT LOTT, Mississippi

OLYMPIA J. SNOWE, Maine

JON KYL, Arizona

CRAIG THOMAS, Wyoming

RICK SANTORUM, Pennsylvania

BILL FRIST, Tennessee

GORDON SMITH, Oregon

JIM BUNNING, Kentucky

MIKE CRAPO, Idaho

MAX BAUCUS, Montana

JOHN D. ROCKEFELLER IV, West Virginia

KENT CONRAD, North Dakota

JAMES M. JEFFORDS (I), Vermont

JEFF BINGAMAN, New Mexico

JOHN F. KERRY, Massachusetts

BLANCHE L. LINCOLN, Arkansas

RON WYDEN, Oregon

CHARLES E. SCHUMER, New York

KOLAN DAVIS, Staff Director and Chief Counsel

RUSSELL SULLIVAN, Democratic Staff Director

(II)

C O N T E N T S

Page

I. Executive Summary ....................................................................................... 1

II. Introduction .................................................................................................... 3

III. Scope and Methodology ................................................................................. 4

IV. Background .................................................................................................... 5

A. Vagus Nerve Stimulation Therapy System ........................................... 5

B. Major Events Related to the Approval of the Vagus Nerve

Stimulation Therapy System for Treatment-Resistant Depression . 6

C. Post-Approval Events .............................................................................. 11

D. Summary of Cyberonics’s Clinical Studies ............................................ 12

V. Discussion ....................................................................................................... 14

A. FDA Official Overruled Review Team: Device Approved Despite

Team’s Objections ................................................................................ 14

B. FDA’s Public Materials Do Not Reveal the Extent of Scientific

Dissent Regarding Effectiveness of Device ........................................ 17

C. Not All Relevant Findings and Conclusions Regarding Safety and

Effectiveness of Device Were Made Publicly Available .................... 24

VI. Concluding Observations ............................................................................... 27

VII. List of Acronyms ............................................................................................ 31

VIII. Glossary .......................................................................................................... 33

IX. Timeline of Major Events Related to Cyberonics’s PMA-Supplement for

the Vagus Nerve Stimulation Therapy System ....................................... 37

X. Appendices ...................................................................................................... 39

Appendix A—Chairman and Ranking Member Letters to the FDA ......... 41

March 11, 2005 ...................................................................................... 42

April 19, 2005 ......................................................................................... 44

May 17, 2005 .......................................................................................... 47

May 27, 2005 .......................................................................................... 48

July 7, 2005 ............................................................................................ 49

July 28, 2005 .......................................................................................... 51

Appendix B—Approval and Labeling Information Posted on FDA’s

Website ....................................................................................................... 55

Approval Order (July 15, 2005) ............................................................ 56

Summary of Safety and Effectiveness .................................................. 63

Physician Labeling ................................................................................ 85

Patient Labeling .................................................................................... 123

CDRH Consumer Information on VNS Therapy System ................... 152

Appendix C—FDA Regulations .................................................................... 155

21 C.F.R. § 10.70 .................................................................................... 156

21 C.F.R. § 10.75 .................................................................................... 157

21 C.F.R. § 812.36 .................................................................................. 159

21 C.F.R. § 814.39 .................................................................................. 162

21 C.F.R. § 814.42 .................................................................................. 164

21 C.F.R. § 814.44 .................................................................................. 165

21 C.F.R. § 814.45 .................................................................................. 166

21 C.F.R. § 814.46 .................................................................................. 167

21 C.F.R. § 814.47 .................................................................................. 168

21 C.F.R. § 814.82 .................................................................................. 169

21 C.F.R. § 860.7 .................................................................................... 170

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Page

IV

Appendix D—Internal FDA Memoranda .................................................... 175

Memoranda related to review of the sponsor’s response to the

FDA’s August 11, 2004, not approvable letter:

Division of General, Restorative, and Neurological Devices,

CDRH (November 10, 2004) ................................................... 176

Division of Neuropharmacological Drug Products, CDER

(October 22, 2004) ................................................................... 186

Product Evaluation Branch II, Division of Postmarket Surveillance, CDRH (November 8, 2004) .................................... 188

Epidemiology Branch, Division of Postmarket Surveillance,

CDRH (November 5, 2004) ..................................................... 195

Division of Biostatistics, CDRH (November 5, 2004) ............... 198

Post-panel Meeting Memorandum (June 22, 2004) ............................ 202

Final Review Team Memorandum (January 6, 2005) ........................ 204

CDRH Director’s Override Memorandum (June 12, 2005) ................. 218

Appendix E—FDA Letters ........................................................................... 239

Initial Review of PMA-S Letter (December 15, 2003) ........................ 240

Major Deficiency Letter (March 1, 2004) ............................................. 243

Not Approvable Letter (August 11, 2004) ............................................ 251

Warning Letter (December 22, 2004) ................................................... 255

Approvable Letter (February 2, 2005) ................................................. 264

Response to Chairman and Ranking Member’s July 7, 2005, Letter

(July 20, 2005) .................................................................................... 272

Response to Chairman and Ranking Member’s July 28, 2005, Letter (August 9, 2005) ........................................................................... 274

Appendix F—E-mail Communications and Other FDA Documents ......... 277

Press release on approval of VNS Therapy for epilepsy (July 16,

1997) .................................................................................................... 278

E-mail from CDER staff to CDRH staff (October 3, 2003) ................. 280

E-mail from CDER psychopharmacology team leader to CDRH review team leader and Branch Chief (February 4, 2004) ................. 281

E-mails from panel members (June 17, 2004, June 18, 2004 and

October 19, 2004) ............................................................................... 282

E-mail from ODE Deputy Clinical Director to ODE Director (September 14, 2004) ................................................................................. 285

E-mail between ODE Deputy Clinical Director and CDER

psychopharmacology team leader (November 24, 2004) ................. 286

E-mail between Branch Chief and review team leader (November

24 and 29, 2004) ................................................................................. 287

E-mail from ODE Deputy Clinical Director to members of review

team (December 22, 2004) ................................................................. 288

E-mail from review team leader to Branch Chief (December 27,

2004) .................................................................................................... 288

E-mail from Director of the Office of Medical Policy to CDRH

Director (December 23, 2004) ............................................................ 289

E-mail from CDER medical reviewer to psychopharmacology team

leader (January 12, 2005) .................................................................. 290

E-mail from ODE Deputy Clinical Director (January 25, 2005) ........ 290

Appendix G—Neurological Devices Panel Meeting .................................... 291

List of Panel Questions ......................................................................... 292

Appendix H—Minutes .................................................................................. 293

Phone Call between FDA and Cyberonics (March 1, 2002) ............... 294

Phone Call between FDA and Cyberonics (October 11, 2002) ........... 297

100-Day PMA-S Meeting (February 4, 2004) ...................................... 298

FDA Review Team Meeting (November 10, 2004) .............................. 302

Appendix I—FDA Advice/Guidance Documents ......................................... 307

CDRH Medical Device Advice Website Materials:

Review Process ............................................................................ 308

Clinical Studies ........................................................................... 319

PMA Supplements and Amendments ........................................ 326

Final Guidance on Least Burdensome Provisions .............................. 337

Appendix J—Technology Evaluation Center, Blue Cross and Blue

Shield Association ..................................................................................... 363

TEC Report (August 2005) .................................................................... 364

Appendix K—CDRH Organizational Chart ................................................ 385

(1)

I. Executive Summary

The United States Senate Committee on Finance (Committee)

has exclusive jurisdiction over the Medicare and Medicaid programs. Accordingly, the Committee has a responsibility to the more

than 80 million Americans who receive health care coverage under

Medicare and Medicaid to oversee the proper administration of

these programs, including the payment for medical devices regulated by the Food and Drug Administration (FDA). Given the rising

health care costs in this country, and more importantly, in the interest of public health and safety, Medicare and Medicaid dollars

should be spent on drugs and devices that have been appropriately

deemed safe and effective for use by the FDA, in accordance with

all laws and regulations.

In February 2005, Senator Charles Grassley (R-IA) and Senator

Max Baucus (D-MT), Chairman and Ranking Member of the Committee, initiated an inquiry into the FDA’s handling of Cyberonics,

Inc.’s (Cyberonics) pre-market approval application to add a new

indication—treatment-resistant depression (TRD)—to Cyberonics’s

Vagus Nerve Stimulation (VNS) Therapy System, an implanted

pulse generator. The Chairman and Ranking Member initiated the

inquiry in response to concerns that were raised regarding

Cyberonics’s VNS Therapy System for TRD. On July 15, 2005, the

FDA approved the device for TRD.

The investigative staff of the Committee reviewed documents and

information obtained and received from the FDA and Cyberonics

and found the following:

• As the federal agency charged by Congress with ensuring that

devices are safe and effective, the FDA approved the VNS

Therapy System for TRD based upon a senior official overruling the comprehensive scientific evaluation of more than 20

FDA scientists, medical officers, and management staff who reviewed Cyberonic’s application over the course of about 15

months. The official approved the device despite the conclusion

of the FDA reviewers that the data provided by Cyberonics in

support of its application for a new indication did not demonstrate a reasonable assurance of safety and effectiveness sufficient for approval of the device for TRD. • The FDA’s formal conclusions on safety and effectiveness do

not disclose to doctors, patients or the general public the scientific dissent within the FDA regarding the effectiveness of

the VNS Therapy System for TRD. The FDA has publicized differences of scientific opinion within the agency when it has announced other controversial regulatory decisions. Throughout

the review of Cyberonics’s application, the team of FDA scientists, medical officers, and management staff involved recommended that the device not be approved for TRD. However,

at every stage of the review, the team was instructed by the

2

1http://www.fda.gov/opacom/morechoices/mission.html.

FDA official, who ultimately made the decision to approve the

device, to proceed with the next stage of pre-market review. • The FDA has not ensured that the public has all of the accurate, science-based information regarding the VNS Therapy

System for TRD it needs. Health care providers relying on the

FDA’s public information on the safety and effectiveness of this

device may not be able to convey complete risk information to

their patients, because not all of the relevant findings and conclusions regarding the VNS Therapy System have been made

available publicly.

The FDA has an important mission:

The FDA is responsible for protecting the public health by

assuring the safety, efficacy, and security of human and

veterinary drugs, biological products, medical devices, our

nation’s food supply, cosmetics, and products that emit radiation. The FDA is also responsible for advancing the

public health by helping to speed innovations that make

medicines and foods more effective, safer, and more affordable; and helping the public get the accurate, science-based

information they need to use medicines and foods to improve their health.1

As part of that mission, the FDA weighs the risks and benefits of

a product, in this case a medical device, to determine if the product

is reasonably safe and effective for use.

The facts and circumstances surrounding the FDA’s approval

process for the VNS Therapy System for TRD raise legitimate

questions about the FDA’s decision to approve that device for the

treatment of TRD. While all implantable medical devices carry

risks, it is questionable whether or not the VNS Therapy System

for TRD met the agency’s standard for safety and effectiveness. The

FDA’s approval process requires a comprehensive scientific evaluation of the product’s benefits and risks, including scientifically

sound data supporting an application for approval. Otherwise

health care providers and insurers as well as patients may question the integrity and reliability of the FDA’s assessment of the

safety and effectiveness of an approved product. In the case of VNS

Therapy for TRD, the FDA reviewers concluded that the data limitations in Cyberonics’s application could only be addressed by conducting a new study prior to approval. However, in the present

case, instead of relying on the comprehensive scientific evaluation

of its scientists and medical officers, it appears that the FDA lowered its threshold for evidence of effectiveness. Contrary to the recommendations of the FDA reviewers, the FDA approved the VNS

Therapy System for TRD and allowed Cyberonics to test its device

post-approval.

In addition, given the significant scientific dissent within the

FDA regarding the approval of the VNS Therapy System for TRD,

the FDA’s lack of transparency with respect to its review of the device is particularly troubling. The FDA has limited the kind and

quality of information publicly available to patients and their doctors and deprived them of information that may be relevant to

3

2 Under 21 C.F.R. § 3.2, the term ‘‘sponsor’’ has the same meaning as ‘‘applicant,’’ any person

who submits or plans to submit an application to the Food and Drug Administration (FDA) for

pre-market review. The sponsor is usually the manufacturer of the product under review, in this

case a medical device manufacturer. Under 21 C.F.R. § 812.3, a sponsor is also a person who

initiates the clinical studies to determine the safety or effectiveness of a device. 3Dow Jones/AP, ‘‘FDA approves implant against depression,’’ July 15, 2005, available at http:/

/www.chron.com/disp/story.mpl/tech/news/3268114.html, last accessed on January 18, 2006.

their own risk-benefit analysis. Patients and their doctors should

have access to all relevant findings and conclusions from the comprehensive scientific evaluation of the safety and effectiveness of

the VNS Therapy System for TRD to enable them to make fully informed health care decisions.

II. Introduction

The United States Senate Committee on Finance (Committee)

has exclusive jurisdiction over the Medicare and Medicaid programs. Accordingly, the Committee has a responsibility to the more

than 80 million Americans who receive health care coverage under

Medicare and Medicaid to oversee the proper administration of

these programs. Given the rising health care costs in this country,

and more importantly, in the interest of public health and safety,

Medicare and Medicaid dollars should be spent on drugs and medical devices that have been appropriately approved by the Food and

Drug Administration (FDA), based on a comprehensive scientific

evaluation of the product’s benefits and risks, in accordance with

all laws and regulations.

On July 15, 2005, the FDA approved Cyberonics, Inc.’s

(Cyberonics or the sponsor 2) Vagus Nerve Stimulation Therapy

System (VNS Therapy System) for a new indication, the first medical device for treatment-resistant depression (TRD). Medicare and

Medicaid currently cover the VNS Therapy System, including programming and implantation of the device, for the treatment of epilepsy, the first indication for which the device was approved.

Cyberonics expects that within a year both programs will also cover

the device for TRD.3

Senator Charles Grassley (R-IA) and Senator Max Baucus (DMT), Chairman and Ranking Member of the Committee, began an

inquiry related to the VNS Therapy System for TRD in February

2005, after allegations of problems with the FDA’s review of

Cyberonics’s device were brought to the attention of the Committee. To review these allegations, the Chairman and Ranking

Member initiated an inquiry and sent a letter to the FDA regarding the FDA’s review of Cyberonics’s pre-market approval application supplement (PMA-S or application) for the use of the VNS

Therapy System for TRD (the sponsor’s PMA-S) in March 2005.

This Committee Staff Report to the Chairman and Ranking

Member (Report) presents the information and findings compiled

by the investigative staff of the Committee (Committee Staff) based

on interviews and the review of documents and information obtained by and provided to the Committee regarding the VNS Therapy System. Appendices to the Report include: correspondence between the Chairman and Ranking Member and the FDA, documentation of the FDA’s internal and external communications regarding the sponsor’s PMA-S, and related materials posted on the

FDA website. The Table of Contents contains a list of documents

4

4Letters from the Chairman and Ranking Member of the Committee to the FDA, see Appendix

A.

in the Appendices. A timeline of major events related to the FDA’s

review of the sponsor’s PMA-S for the VNS Therapy System are

also included at the end of this Report.

III. Scope and Methodology

During the course of its inquiry, the Committee Staff obtained

numerous documents related to the FDA’s review of Cyberonics’s

PMA-S for the VNS Therapy System for TRD, including documents

that contain clinical data submitted by the sponsor to the FDA as

part of its application. The Committee Staff did not independently

assess the validity of the data submitted or determine whether or

not the sponsor met the FDA’s standards for approval of the VNS

Therapy System. The purpose of the Chairman and Ranking Member’s inquiry was to address the allegations, examine the FDA’s review of the sponsor’s PMA-S, and consider whether or not Medicare

and Medicaid dollars should be spent on a drug or device because

it has received FDA approval.

In addition, several individuals who were interviewed by the

Committee Staff raised concerns about the FDA’s process for premarket review and post-market surveillance of medical devices generally. A range of allegations regarding the FDA and Cyberonics as

well as medical devices in general were brought to the attention of

Committee Staff; however, this Report is limited to those allegations most germane to the Committee Staff’s initial review of the

FDA’s approval process for the VNS Therapy System for TRD.

Other allegations may be addressed at a later date. This Report focuses solely on matters and events related to the sponsor’s PMAS and how the FDA made the decision to approve the VNS Therapy

System for TRD.

By letters dated March 11, April 19, May 17, May 27, July 7, and

July 28, 2005, the Chairman and Ranking Member requested from

the FDA documents and information related to the FDA’s review

and approval of the VNS Therapy System for TRD, as well as

interviews with FDA staff involved in the review.4 The Committee

Staff review was conducted from February through September

2005.

In conducting the inquiry, the Committee Staff:

• Interviewed eleven FDA employees; six of whom were directly

involved in the review of the VNS Therapy System for TRD

and internal deliberations regarding the sponsor’s PMA-S.

• Reviewed documents provided by the FDA, which were created

during the course of the FDA’s review of the sponsor’s PMAS.

• Reviewed documents from the sponsor, which were produced

voluntarily to the Committee by the sponsor, including filings

in support of its PMA-S, e-mail communications, meeting minutes, and other documentation of internal communications, as

well as communications between the FDA and the sponsor related to the review of the VNS Therapy System for TRD.

5

5FDA’s overview of the VNS Therapy System, see Appendix B; also available at http://

www.fda.gov/cdrh/mda/docs/p970003s050.html. 6FDA’s July 16, 1997, press release on the approval of the VNS Therapy System for the treatment of epilepsy, see Appendix F; also available at http://www.fda.gov/bbs/topics/NEWS/

NEW00576.html. 7 Approval letter issued to the sponsor on July 15, 2005, see Appendix B; also available at

http://www.fda.gov/cdrh/PDF/p970003s050a.pdf. 8 Electroconvulsive therapy is a type of shock therapy that involves a brief electrical shock

that is applied to the head to induce a short seizure. For more information, see http://

www.nlm.nih.gov/medlineplus/ency/article/003324.htm. 9 Available at http://www.fda.gov/cdrh/mda/docs/p970003s050.html; see also Appendix B.

• Examined FDA regulations regarding medical device review,

documentation of contacts with sponsors, and conditional approvals.

IV. Background

A. Vagus Nerve Stimulation Therapy System

The VNS Therapy System is an implanted vagus nerve stimulator.5 The FDA initially approved the VNS Therapy System in

July 1997 for epilepsy to help reduce seizures that could not be

fully or adequately controlled by drugs or surgery.6 By letter dated

July 15, 2005, the FDA approved the VNS Therapy System ‘‘indicated for the adjunctive long-term treatment of chronic or recurrent

depression for patients 18 years of age or older who are experiencing a major depressive episode and have not had an adequate

response to four or more adequate antidepressant treatments.’’ 7

The FDA website (www.fda.gov) provides an overview of the VNS

Therapy System, which consists of a pulse generator that is surgically implanted under the skin of the left chest and an electrical

lead that is connected from the generator to the left vagus nerve.

Electrical signals are sent from the battery-powered generator to

the vagus nerve via the lead. To turn the stimulator off, the patient

holds a magnet over the pulse generator. The overview provides information regarding usage of the device:

The device is to be used only in patients 18 years of age

or over with treatment-resistant depression. These are patients who have been treated with, but failed to respond

to, at least 4 adequate medication and/or [electroconvulsive

therapy] ECT 8 treatment regimens prescribed by their

physician. It is not intended to be used as a first-line treatment, even for patients with severe depression. It should

be prescribed and monitored only by physicians who have

specific training and expertise in the management of treatment-resistant depression and the use of this device. It

should be implanted only by physicians who are trained in

surgery of the carotid sheath and have received specific

training in the implantation of the device. . . . The device

cannot be used in patients who have had their vagus nerve

cut or will be exposed to diathermy.9

According to the physician and patient labeling for the VNS

Therapy System for TRD, commonly reported side effects associated with the use of the device in epilepsy patients and patients

with depression include voice alteration, increased cough, dyspnea

(shortness of breath), neck pain, and dysphagia (difficulty swalVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00013 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
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10The Physician and Patient Labelings for the VNS Therapy System for TRD are available

at http://www.fda.gov/cdrh/PDF/P970003S050.html; see also Appendix B. 11 According to the National Institutes of Health’s National Institute of Neurological Disorders

and Stroke, sleep apnea is a common sleep disorder characterized by brief interruptions of

breathing during sleep. For more information, see http://www.ninds.nih.gov/disorders/sleep—

apnea/sleep—apnea.htm. 12 21 C.F.R. § 814.39(a)(1), see Appendix C; see also Congressional Research Service, The U.S.

Approval Process for Medical Devices: Legislative Issues and Concerns with the Drug Model,

RL32826 (March 23, 2005), available at http://www.congress.gov/erp/rl/pdf/RL32826.pdf. 13Pub. L. No. 105–115, 111 Stat. 2296, 2336–2338. 14Food and Drug Administration, ‘‘The Least Burdensome Provisions of the FDA Modernization Act of 1997: Concept and Principles; Final Guidance for FDA and Industry,’’ October 4,

2002, see Appendix I; also available at http://www.fda.gov/cdrh/ode/guidance/1332.pdf. 15 21 C.F.R. § 860.7, see Appendix C. 16 21 C.F.R. § 860.7(d)(1), see Appendix C. 17 21 C.F.R. § 860.7(e)(1), see Appendix C.

lowing).10 Serious adverse events that have been reported include

death, cardiac events, vocal cord paralysis, sleep apnea,11 and

worsening depression.

B. Major Events Related to the Approval of the Vagus Nerve

Stimulation Therapy System for Treatment-Resistant

Depression

On October 27, 2003, the sponsor submitted a PMA-S to the FDA

to add treatment-resistant depression as a new indication for the

VNS Therapy System. Once a device has been cleared through the

PMA process, a device manufacturer can file additional information

with the FDA as a supplement to the original PMA to demonstrate

that an already-approved device is safe and effective for a new indication.12 In the case of the VNS Therapy System, the original PMA

was approved in 1997 for commercial distribution of the device for

the treatment of epilepsy.

In 1997, Congress also passed the Food and Drug Administration

Modernization Act (FDAMA) to streamline the FDA approval process for medical devices,13 among other things, to ‘‘ensure the timely

availability of safe and effective new products that will benefit the

public.’’ According to FDA guidance on the new provisions that

were added to the Federal Food, Drug, and Cosmetic Act as a result of FDAMA, ‘‘While Congress wanted to reduce unnecessary

burdens associated with the premarket clearance and approval

processes, Congress did not lower the statutory criteria for demonstrating . . . reasonable assurance of safety and effectiveness.’’ 14

The FDA’s standard for approval of an implantable device is

‘‘reasonable assurance of safety and effectiveness.’’ 15 The FDA considers there to be a reasonable assurance of safety when it can be

determined that the probable benefits to health that result from

the use of the device as directed by the sponsor and accompanied

by adequate instructions for use and warnings against unsafe use

outweigh any probable risks.16 The FDA considers there to be a

reasonable assurance of effectiveness when, based upon valid scientific evidence, the use of the device in a significant portion of the

target population according to the sponsor’s instructions will

produce clinically significant results.17

Once the FDA receives a PMA-S, a team of FDA scientists and

medical officers is assigned to review the application. The review

team assigned to Cyberonics’s PMA-S consisted of more than a

dozen FDA scientists and medical officers from the Center for DeVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00014 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
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18Members of the review team include staff from the Division of General, Restorative and

Neurological Devices in the Office of Device Evaluation, the Division of Bioresearch Monitoring

in the Office of Compliance, and the Division of Biostatistics and Surveillance and the Division

of Postmarket Surveillance in the Office of Surveillance and Biometrics. See CDRH organizational chart, Appendix K. 19Members of the review team include staff from the Division of Neuropharmacological Drug

Products in the Office of Drug Evaluation I. 20 In the summer of 2005, the Division of Neuropharmacological Drug Products was split into

two divisions within the Office of Drug Evaluation I, the Division of Neurology Products and

the Division of Psychiatry Products. 21 21 C.F.R. § 814.42(a), see Appendix C. 22The filing date is the date on which the FDA received the sponsor’s PMA-S, October 27,

2003. 23Letter to the Director and Senior Counsel, Regulatory Affairs, Cyberonics, Inc. signed by

the Director of the Division of General, Restorative and Neurological Devices, Office of Device

Evaluation, CDRH, December 15, 2003, see Appendix E. 24Food and Drug Administration, U.S. Department of Health and Human Services, ‘‘Guidance

for Industry and FDA Staff: Expedited Review of Premarket Submissions for Devices,’’ November 26, 2003, available at http://www.fda.gov/cdrh/mdufma/guidance/108.html. 25 CDRH Device Advice website, http://www.fda.gov/cdrh/devadvice/pma/review—

process.html; see also Appendix I.

vices and Radiological Health (CDRH) 18 and the Center for Drug

Evaluation and Research (CDER).19 This team included neurosurgeons, neurologists, psychiatrists, statisticians, epidemiologists,

and adverse events analysts. Management staff of the Restorative

Devices Branch, the Division of General, Restorative and Neurological Devices (DGRND), and the Office of Device Evaluation

(ODE) in CDRH and the Division of Neuropharmacological Drug

Products 20 and the Office of Drug Evaluation I in CDER were also

involved in the review of the sponsor’s PMA-S.

After a sponsor submits its PMA-S, the review team determines

whether or not that sponsor provided the required administrative

components of the PMA-S. The FDA has 45 days to make sure an

application is administratively complete.21 If an application is complete, the FDA formally files it and begins its substantive review.

By letter dated December 15, 2003, the FDA informed Cyberonics

that its PMA-S was suitable for filing 22 and granted expedited review because ‘‘the VNS Therapy System has the potential of providing therapeutic benefits . . . in the treatment of patients who are

intolerant or resistant to other legally marketed therapies.’’ 23 FDA

guidance states that a device is appropriate for expedited review if

the device is (1) intended to treat or diagnose a life-threatening or

irreversibly debilitating disease or condition, and (2) addresses an

unmet medical need.24

The CDRH website states that during the PMA review process,

the FDA notifies a sponsor by major/minor deficiency letters of any

information needed by the FDA to complete its review. In addition,

a sponsor can request a meeting with the FDA within 100 days of

the filing of its application to discuss the status of the FDA’s review.25 According to the FDA review team leader for Cyberonics’s

PMA-S, on February 4, 2004, 100 days after the sponsor filed its

application, the FDA held a meeting with the sponsor to discuss

concerns or questions related to the sponsor’s PMA-S. The team

leader stated that the sponsor did not address all the concerns discussed during the 100-day meeting; and that the 23 concerns not

addressed were identified in a major deficiency letter that the FDA

sent to the sponsor on March 1, 2004. In that letter, the FDA statVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00015 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
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26For example, the FDA stated that according to the National Depressive and Manic Depressive Association Consensus panel, ‘‘patients with mood disorders have inherently high placebo

response rates, and without a placebo (control) or valid alternative method, . . . most findings

are difficult to interpret.’’ Because the sponsor’s only placebo-controlled study failed, the FDA

asked the sponsor to provide any additional information that would address the potential bias

that may occur from a placebo effect. See Appendix E for the text of the major deficiency letter.

A ‘‘placebo’’ is an inactive substance or treatment against which investigational treatments are

compared for efficacy and safety. A ‘‘placebo-controlled study’’ is a study in which an inactive

substance or treatment (placebo) is given to one group of patients, while the treatment being

tested is given to another group. High placebo response rate, or ‘‘placebo effect’’ is a physical

or emotional change, such as an improvement in health or alleviation of symptoms, that is not

the result of any special property of the treatment received but may occur because individuals

expect or believe that the treatment will work. 27See Congressional Research Service, The U.S. Approval Process for Medical Devices: Legislative Issues and Concerns with the Drug Model, RL32826 (March 23, 2005), available at http:/

/www.congress.gov/erp/rl/pdf/RL32826.pdf. According to the CDRH Device Advice website on

the PMA review process, all PMAs for a first-of-a kind device are generally referred to an advisory panel for review and recommendation. Once the FDA believes that ‘‘(1) the pertinent issues

in determining the safety and effectiveness for the type of medical device are understood and

(2) FDA has developed the ability to address those issues,’’ future PMAs for that type of device

are not taken before a panel unless there is an issue that can be best addressed through panel

review. See http://www.fda.gov/cdrh/devadvice/pma/review—process.html. A copy of the review process overview is included in Appendix I. 28The other questions were: (1) whether or not data that are not derived from a randomized

study affect the evaluation of the effectiveness of the VNS Therapy System for TRD, i.e., a study

where the subjects are randomly assigned to VNS Therapy and no VNS Therapy; (2) whether

or not the clinical outcomes of one of the sponsor’s major studies were the result of a ‘‘placebo

effect’’; and (3) whether or not the use of antidepressant medications and electroconvulsive therapy in conjunction with VNS Therapy impact the interpretation of the study results on the effectiveness of the VNS Therapy System for treatment-resistant depression. See Appendix G for the

list of panel questions.

ed that its review of the PMA-S could not continue until the sponsor addressed the 23 deficiencies described therein.26

Once a sponsor addresses the concerns and questions identified

in a major deficiency letter, the review team can complete its initial

review of the PMA-S and determine whether or not to proceed with

an advisory panel to obtain input and recommendations from outside experts on the approvability of the device.27 In the case of

VNS Therapy, the Committee Staff were told that the review team

did not believe that the sponsor had satisfactorily addressed all of

the deficiencies. However, the Director of ODE, who became the

Acting Director of CDRH in May 2004 and the Director in August

2004, instructed the review team to proceed with an advisory panel

meeting. On June 15, 2004, the FDA Neurological Devices Panel

was held to address several questions from the FDA regarding the

sponsor’s PMA-S, including whether or not the clinical data in the

PMA-S provided a reasonable assurance of safety and effectiveness.28 The panel recommended, by a vote of five to two, that the

device be approved with the following conditions:

(1) Patients should fail four or more traditional treatment

modalities for TRD (i.e., antidepressant medications or

electroconvulsive therapy (ECT)) before using the VNS Therapy System for TRD.

(2) The device should be implanted by surgeons with appropriate training.

(3) Training regarding the programming of the device should

be provided to primary care providers.

(4) The product should have additional patient labeling to inform patients completely of the risks and benefits involved in

having the device implanted and an identification card should

be provided to patients that indicate they have the device implanted.

9

29The transcript of the June 15, 2004, Neurological Devices Panel meeting is available at

http://www.fda.gov/ohrms/dockets/ac/04/transcripts/2004-4047t1.htm. 30 Not Approvable Letter, see Appendix E. 31 21 C.F.R. § 814.44(f), see Appendix C. 32 21 C.F.R. § 10.75, see Appendix C; the Ombudsman and several other FDA staff informed

the Committee Staff that the last option is rarely used. 33 21 C.F.R. § 812.36, see Appendix C.

(5) A patient registry to collect clinical data should be established.

(6) The patient labeling should be revised regarding, among

other things, the description of the 12 month open label followup study and the variable effect of treatment.29

The FDA considers an advisory panel’s recommendations in deciding whether or not to approve a device; however, panel recommendations are not binding. In this case, although the advisory

panel recommended conditional approval, the FDA issued a not approvable letter to the sponsor on August 11, 2004.30 According to

the FDA, a not approvable letter means that the FDA found the

data provided by the sponsor insufficient to establish that there is

a reasonable assurance that the device is safe and/or effective for

the use(s) specified in the sponsor’s application.

FDA regulations state that, after a sponsor receives a not approvable letter, the sponsor may amend its PMA as outlined in the

not approvable letter, request an administrative review by filing a

petition for reconsideration under 21 C.F.R. § 10.33, or withdraw

its application.31 The FDA Ombudsman for CDRH informed the

Committee Staff that, in practice, the sponsor has several options

if it wants to continue to seek approval for its product. The sponsor

can submit an amendment to the PMA-S to address the problems

identified in the not approvable letter; the sponsor can petition the

FDA to reconsider its decision; the sponsor can appeal up the supervisory chain; or the sponsor can file a formal appeal of the decision to the dispute resolution panel.32

In this case, Cyberonics requested that the FDA reconsider the

not approvable decision, but after examining additional data provided by the sponsor, the ODE Director concluded that there was

no basis for reconsideration. Consequently, on September 23, 2004,

the sponsor submitted an amendment to its PMA-S (Amendment)

to address the deficiencies identified in the August 11, 2004 not approvable letter. The Amendment included analyses of additional

data from studies conducted by the sponsor to examine the responses of TRD patients to VNS Therapy.

In addition to its Amendment, on September 10, 2004, the sponsor submitted a request for a Treatment Investigational Device Exemption (Treatment IDE) to the FDA. A Treatment IDE allows a

device that is not yet approved for marketing to be used to treat

patients with a serious or immediately life-threatening disease or

condition when no comparable or satisfactory alternative device or

treatment is available. ‘‘The purpose is to facilitate the availability

of promising new devices to desperately ill patients as early in the

device development process as possible, . . . and to obtain additional data on the device’s safety and effectiveness.’’ 33 The device

must be under investigation in a clinical trial for the same use, or

the clinical trials are completed but the sponsor is pursuing marketing approval of the device. The FDA conditionally approved the

10

34Patients are randomly assigned to different treatment groups, and neither the study investigator nor the patient knows to which treatment group the patient has been assigned. 35 21 C.F.R. Part 820. 36See Appendix E for the full text of the warning letter. 37 According to FDA regulations, the FDA sends a manufacturer an approvable letter if the

manufacturer’s application substantially meets the requirements of FDA regulations, and the

FDA believes it can approve the application if the manufacturer provides additional information

or agrees to certain conditions specified by the FDA, such as product labeling and post-approval

requirements, 21 C.F.R. § 814.44, see Appendix C.

sponsor’s Treatment IDE on September 22, 2004. On October 1,

2004, the sponsor submitted an IDE Supplement to address deficiencies identified in FDA’s conditional approval, and the FDA approved the IDE Supplement on October 15, 2004.

Over the next few months, the sponsor continued to meet and

communicate with FDA officials regarding the Amendment. On December 1, 2004, the CDRH Director convened a meeting between

members of the FDA review team and the sponsor’s clinical, statistical, legal, and management staff. According to the team leader

and DGRND Director, only four members of the review team were

invited to the meeting; the management staff at the branch and division levels who were involved in the review of the sponsor’s PMAS were not invited to attend. The purpose of the meeting was to

further discuss the deficiencies listed in the August 11, 2004, not

approvable letter and consider options to obtain FDA approval, including options for another pre-market study or a commitment

from the sponsor to conduct additional studies once the device was

approved. After the meeting, the sponsor submitted proposals for a

randomized, double-blind 34 comparison study to be conducted postapproval. Based on a review of communications and documents provided to and obtained by the Committee Staff, there were no preapproval studies proposed or discussed with the sponsor after December.

In addition to the review of a sponsor’s PMA, the FDA inspects

the sponsor’s operations and records to ensure that medical devices

are designed, manufactured and distributed in compliance with the

Current Good Manufacturing Practices (CGMP) requirements of

the Quality System Regulation 35 and other standards. During an

interview with Committee Staff, the ODE Director stated that it

was not unusual for the FDA to clear a PMA but not approve the

device because the sponsor fails an inspection. On December 22,

2004, the FDA issued a warning letter to the sponsor identifying

a number of significant violations of the Quality System Regulation, including a failure to establish and maintain adequate procedures for validating device design, failure to completely investigate

and evaluate the case of each adverse event, and failure to establish and maintain procedures for implementing corrective and preventive actions.36 On January 21, 2005, the sponsor submitted its

response to the warning letter, and on April 6, 2005, the sponsor

was notified that its response was complete.

On February 2, 2005, the FDA issued an approvable letter to the

sponsor, which superceded the not approvable letter issued on August 11, 2004.37 An approvable letter is not a final approval. However, if the FDA determines that the sponsor has met the conditions outlined in the approvable letter, the device can be approved

for the specified use. The conditions outlined in Cyberonic’s approvable letter included conducting two post-approval studies: (1) estabVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00018 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
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38See Appendix E for the full text of the approvable letter. 39See 21 C.F.R. § 814.82, Appendix C. 40 CPT Codes describe the medical or psychiatric procedures performed by health care providers. 41D. Mark, ‘‘Vagus Nerve Stimulation for Treatment-Resistant Depression,’’ August 2005, see

Appendix J; also available at http://www.bcbs.com/tec/vol20/20—08.html. 42 According to the TEC website (http://www.bcbs.com/tec/), the TEC uses five criteria to assess whether a technology improves health outcomes: (1) The technology must have final approval from the appropriate governmental regulatory bodies; (2) the scientific evidence must permit conclusions concerning the effect of the technology on health outcomes; (3) the technology

must improved the net health outcome; (4) the technology must be as beneficial as any established alternatives; and (5) the improvement must be attainable outside the investigative settings.

lishing a registry of 1,000 TRD patients implanted with the vagus

nerve stimulator and evaluating their response to the therapy for

five years after implantation; and (2) conducting a randomized,

double-blind comparison of different output of currents from the device in 450 TRD patients with follow-up for at least one year after

implantation to determine the optimal dosage of stimulation in patients with TRD. The FDA also required the sponsor to submit revised physician and patient labelings for the VNS Therapy System

for TRD and to address any deficiencies identified during FDA inspections of the sponsor’s clinical study sites. In addition, the sponsor was informed that the PMA-S could not be approved until the

FDA determined that the manufacturing facilities, methods, and

controls complied with the conditions set forth in the sponsor’s application and the applicable requirements of the Quality System

Regulation.38

On July 15, 2005, the CDRH Director signed the approval letter

for the VNS Therapy System for TRD. The approval letter allows

the sponsor to begin commercial distribution of the VNS Therapy

System for TRD; however, as specified in the February 2, 2005 approvable letter, the sponsor must meet certain conditions, including

two post-approval studies.39

C. Post-Approval Events

Since the approval of the VNS Therapy System for TRD in July

2005, the sponsor has initiated efforts to secure reimbursement for

the use of its device to treat TRD. In September 2005, the American Medical Association’s Current Procedural Terminology 40

(CPT) Editorial Board approved the use of the same neurostimulator programming codes that are currently being used for

VNS Therapy programming services for patients with epilepsy for

the treatment of patients with TRD.

In addition, the BlueCross BlueShield Technology Evaluation

Center (TEC), which provides scientific opinions regarding the clinical effectiveness and appropriateness of specific medical procedures, devices, and drugs, published its assessment of the VNS

Therapy System for TRD in August 2005.41 The TEC examined the

available evidence on the effectiveness of the VNS Therapy System

for TRD, including findings from three of the sponsor’s clinical

studies, and concluded that ‘‘Overall, the evidence supporting efficacy of VNS is not strong.’’ 42 Based on the evidence it reviewed,

the TEC determined that the VNS Therapy System did not meet

12

43The TEC reviewed published and unpublished data related to the clinical outcomes of the

VNS Therapy System for TRD. The sponsor’s response to the TEC assessment is available

on its VNS Therapy for TRD website at http://www.vnstherapy.com/depression/hcp/

ReimbursementIns/data.aspx. 44Physicians use a device ‘‘off-label’’ when they prescribe an FDA-approved product for treatments other than those specified on the product labeling. 45See Appendix B, Summary of Safety and Effectiveness, p. 68, and Physician Labeling,

p. 110. 46 21 C.F.R. § 860.7(e), see Appendix C.

all of its criteria for demonstrating that the device improves health

outcomes, such as length of life and quality of life.43

D. Summary of Cyberonics’s Clinical Studies

After a device is approved for marketing by the FDA, a potential

new use for the device may be discovered through observations

from additional clinical trials or by health care providers in the

course of using the device as approved by the FDA or off-label to

treat their patients.44 According to the FDA review team leader on

the sponsor’s PMA-S, after the VNS Therapy System was approved

for epilepsy in 1997, anecdotal reports of mood alteration were

noted in some of the epilepsy patients implanted with the vagus

nerve stimulator.

To investigate these reports, the sponsor conducted a pilot study

(D–01) of 60 patients with treatment-resistant depression to examine their response rates to the device. D–01 was an open-label, nonrandomized, single-treatment arm study—all 60 patients were implanted with the device and were aware that they were receiving

VNS Therapy. The study had no control groups, i.e., patients without the device implanted or patients with an inactive device, so patient response rates could not be compared. VNS Therapy was used

as an adjunctive treatment, so patients continued their antidepressant medication regimen during the study. The study consisted of a 12-week (after implantation) acute phase and a longterm follow-up. A health care provider-administered screening tool

known as the Hamilton Rating Scale for Depression (HRSD) was

used to rate the severity of depression; the higher the score, the

more severe the depression. The sponsor defined a response to the

VNS Therapy System as a 50 percent or greater reduction in the

HSRD score. Based on this definition, at the end of 12 weeks, 18

of 59 patients (31 percent) responded to the device. After one and

two years of VNS Therapy in conjunction with antidepressant

medication and/or ECT treatment regimens, 25 of 55 (45 percent)

and 18 of 42 (43 percent) patients, respectively, exhibited a response.45

As mentioned previously, a sponsor can file a supplement to an

original PMA to obtain approval for a new indication for a device.

To obtain FDA approval for the new indication, the sponsor must

demonstrate a reasonable assurance that the device is safe and effective for the new indication. According to FDA regulations, reasonable assurance of effectiveness must be based on ‘‘valid scientific evidence.’’ 46 Valid scientific evidence consists principally of

well-controlled clinical investigations, which include assigning

study subjects to tests groups that can be compared. The regulations specify four types of controls to which subjects receiving the

treatment under investigation can be compared: (1) no treatment;

(2) placebo control, e.g., an implanted device that has not been actiVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00020 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
13

47 21 C.F.R. § 860.7(f), see Appendix C.

vated used under conditions that resemble the conditions of use

under investigation; (3) active treatment control, i.e., comparison to

an effective treatment; and (4) historical control, i.e., comparison to

a group of patients receiving no treatment or an established effective regimen who were observed at a previous time.47

To address the requirement of ‘‘valid scientific evidence,’’ the

sponsor conducted a second study, a randomized, placebo-controlled

study (D–02), to examine the difference in responses to VNS Therapy over a 12-week period between patients with TRD whose devices were activated compared to those whose devices were not activated. In this first phase of D–02, also known as the acute phase,

all study participants were implanted with the device, but 119 patients had the device activated (the treatment group) and 116 patients did not (the placebo control group). The patients were randomly assigned to the treatment group or the control group. Patients were allowed to continue the antidepressant treatments that

they were already receiving, but changes to those treatment regimens were not allowed during the course of the study. After 12

weeks, based on the HSRD scores, about 15 percent of the treatment group responded compared to 10 percent of the control group;

however, because the difference observed was not ‘‘statistically significant,’’ any differences observed between the two groups of patients could have been due to chance rather than a response to the

device.

The second phase of D–02 was a long-term follow-up. In this

phase, all of the inactive devices that were implanted in the patients during the acute phase of D–02 were turned on, so the study

lost its placebo control group. The sponsor used a population of 124

patients from a different study (D–04) to act as a comparison

group. D–04 was a long-term, observational study, in which patient

responses to the usual standard of care for people with a major depressive episode—antidepressant medications and/or ECT—were

observed and noted by the study investigators.

In the long-term phase of D–02, there were no restrictions on

changing patients’ antidepressant treatment regimens during the

course of the study, which were taken in conjunction with VNS

Therapy. After 12 months, about 30 percent of the D–02 patients

had a 50 percent or greater reduction in their HSRD scores. About

22 percent responded based on a different screening tool used by

the sponsor to assess patient response rates, the Inventory of Depressive Symptomatology-Self-Report (IDS-SR). Unlike the HSRD,

the IDS-SR is not administered by a health care provider. The response rates for the D–04 patients at 12 months were 12 percent

(IDS-SR) and 13 percent (HSRD). In addition, the sponsor examined the level of sustained response in D–02 compared to D–04 patients and found a statistically significant difference between the

two groups—13 percent of the D–02 patients evaluated had a sustained response compared to 4 percent in the D–04 group. Sustained response was defined as a 50 percent improvement or better

in the IDS-SR scores at 9 months and 12 months.

14

48The VNS Therapy System is approved in the European Union and Canada for use in the

treatment of TRD. 49See Appendix B for the FDA’s Summary of Safety and Effectiveness, which provides, among

other things, additional results and details from these studies, pp. 68, 71–82. 50 In the Preamble to a final rule amending the FDA’s regulations governing the content and

format of labeling for human prescription drug and biological products, the FDA recently asserted the following:

Under the act and FDA regulations, the agency determines that a drug is approvable

based not on an abstract estimation of its safety and effectiveness, but rather on a comprehensive scientific evaluation of the product’s benfits and risks under the conditions of

use prescribed, recommended, or suggested in the labeling.

Although the final rule relates to drug and biological products, the import of the policy statement articulated by the FDA bears directly on the facts, circumstances, and findings of this Report. See ‘‘Requirements on Content and Format of Labeling for Human Prescription Drug and

Biological Products,’’ 71 Fed. Reg. 3922, 3934 (January 24, 2006) (to be codified at 21 C.F.R.

pts. 201, 314, and 601). 51Final review team memorandum, see Appendix D, p. 205.

In addition to the D–02/D–04 comparative study, the sponsor

submitted data from three other studies to support its application

for FDA approval to market the VNS Therapy System for TRD. D–

03 was a Phase IV European post-market study in 47 patients with

chronic or recurrent depression.48 D–05 was not a clinical study

but a videotape assessment of D–02 patients, and D–06 was a clinical study examining VNS Therapy in seven patients with bipolar

disorder.

The FDA’s not approvable and approval decisions regarding the

safety and effectiveness of the VNS Therapy System for TRD were

based primarily on the FDA’s evaluation of data collected from the

D–01, D–02 and D–04 studies.49

V. Discussion

A. FDA Official Overruled Review Team: Device Approved Despite

Team’s Objections

In February 2005, after the FDA issued an approvable letter to

the sponsor, concerns were raised regarding FDA’s review of the

sponsor’s PMA-S for the VNS Therapy System for TRD. Specifically, it was alleged that the CDRH Director signed an approvable

letter despite strong objections from the FDA review team for the

sponsor’s PMA-S and the DGRND and ODE management staff involved in the review. The FDA reviewers concluded that based on

the data provided to the FDA in the PMA-S, the sponsor did not

demonstrate a reasonable assurance of safety and effectiveness for

approval of the device for TRD. Nevertheless, the CDRH Director

decided that the VNS Therapy System should be approved for TRD

and the FDA issued an approval letter to the sponsor on July 15,

2005.50

In interviews with Committee Staff, the review team leader, the

DGRND Director, the ODE Deputy Clinical Director, and the ODE

Director all expressed concerns regarding the CDRH Director’s decision to conditionally approve the VNS Therapy System for TRD.

The review team recommended that the device not be approved for

TRD because the team determined, over the course of about 15

months, the sponsor did not provide ‘‘a reasonable assurance that

the probable benefits to health from use of the device for its intended uses and conditions outweigh the risks associated with its

use.’’ 51 According to an FDA medical officer who was involved in

the review of the sponsor’s PMA-S, ‘‘surgically implanted devices

15

52Post-panel meeting memorandum from a medical officer on the review team to the team

leader for the Administrative File of the sponsor’s PMA-S, June 22, 2004, see Appendix D,

p. 202. 53Final review team memorandum, see Appendix D, pp. 215–216. 54Final review team memorandum, see Appendix D, p. 216. 55Final review team memorandum, see Appendix D, p. 216. 56See Appendix I for minutes from the November 10 meeting, which include summaries of

the concerns and issues raised by team members representing other divisions and offices within

CDRH as well as concerns raised by the Division of Neuropharmacological Drug Products within

Continued

carry known risks including infection, need for future removal of

the device, and injury to structures in and around the operative

site (specifically vagal and recurrent laryngeal nerve injury) as well

as the risk of anesthesia, which is also significant. In order to outweigh these risks, a device must demonstrate efficacy.’’ 52

During interviews with Committee Staff, the FDA staff stated

that decisions regarding the approval or non-approval of medical

devices are typically made at the division level of CDRH, unless

the device is the first of its kind or the device is being reviewed

for a new indication. Under those circumstances, the ODE Director

signs the letter of approval or non-approval, although the ODE Director informed Committee Staff that she typically reads only the

review team’s internal review memorandum before she makes a decision. The review memorandum documents a team’s rationale for

recommending approval or non-approval of a device. In the case of

VNS Therapy for TRD, the review of the application was elevated

from the division level (DGRND), to the office level (ODE), and finally to the center level (CDRH).

The review team’s final review memorandum, dated January 6,

2005, recommended that the VNS Therapy System not be approved

for TRD.53 This memorandum was approved and signed by the

team leader, the Restorative Devices Branch Chief, the DGRND

Deputy Director and Director, and, atypically, included the signature of the ODE Director. The ODE Director informed Committee

Staff that the internal review memorandum only provides signature lines for the team leader, branch chief, deputy division director and division director.54

Because the review of the sponsor’s PMA-S had been elevated to

the ODE level, the August 11, 2004, not approvable letter was

signed by the ODE Director. During an interview, the ODE Director informed Committee Staff that she added her signature to the

review team’s January 2005 memorandum when she realized that

the Center Director would likely be overriding the not approvable

decision.55 She explained that she wanted to make clear her concurrence with the rest of the review team that the VNS Therapy

System for TRD should not be approved because the data provided

by the sponsor were insufficient to meet the standard of reasonable

assurance of safety and effectiveness.

The review team was not convinced that the additional data provided by the sponsor as part of its Amendment submission were

sufficient for approval. After reviewing the data, the review team

met on November 10, 2004, to discuss the submission and vote on

whether the sponsor’s application should be approved, conditionally

approved, or considered not approvable. Aside from one abstention,

the members of the review team who were present at the meeting

unanimously recommended that the device not be approved.56

16

CDER. See also memoranda included in Appendix D for more detailed discussions of the concerns and issues raised by the review team members related to the sponsor’s response to the

August 11, 2004 not approvable letter. 57See Appendix F. 58 Ibid. 59 Ibid.

In addition to the internal review memorandum and meeting

minutes, the team leader and the ODE Deputy Clinical Director expressed concerns regarding approval of VNS Therapy for TRD in

e-mail communications to other members of the team. After informing the team leader and several other members of the review team

that the CDRH Director would be making the decision regarding

approval, the ODE Deputy Clinical Director wrote in an e-mail

dated December 22, 2004:

It will be tough for most if not all of us to look at a postapproval study . . . since we don’t agree with the approval

decision.57

When the review team leader became aware that the CDRH Director was ‘‘leaning towards approval,’’ he requested that the review

of submissions related to VNS Therapy for TRD be reassigned to

another FDA reviewer. In an e-mail dated December 27, 2004, he

wrote:

Considering my scientific recommendation of not approvable based on the lack of clinical data supporting a reasonable assurance of safety or effectiveness and my knowledge

of the ethical uncertainty in how they may have collected

data in their epilepsy registry, I believe I have little to

contribute in either the proposed dosage study or the postmarket registry.58

In another message from the ODE Deputy Clinical Director to the

team leader and several other members of the review team dated

January 25, 2005, he wrote:

I think it is clear down here that [the CDRH Director] is

going to approve VNS for Depression. . . . I know that both

of you believe this product should not be approved (as do

I) but [the CDRH Director] is asking us to at least make

sure there is truth in the labeling and I think that can be

done regardless of our individual takes on the approvable/

not approvable decision.59

CDER staff involved in the PMA-S review were also concerned

about the VNS Therapy System being approved by CDRH for TRD.

In an e-mail dated January 12, 2005, a CDER medical reviewer

stated:

I am disturbed that VNS might actually get an approval

for ‘‘TRD’’. In my opinion, they do not have adequate data

and I don’t understand how this can move forward. I think

you feel much the same but what will happen if the postapproval study is negative? Will the device be withdrawn?

And, more importantly, it seems this type of data should

come before approval.

17

60See Appendix F. 61 21 C.F.R. § 10.70 requires documentation of significant agency decisions in an administrative file. The administrative file must contain, among other things, ‘‘the recommendations and

decisions of individual employees, including supervisory personnel, responsible for handling the

matter,’’ see Appendix C. 62Medical devices are classified based on the risk they pose when patients use or misuse

them. There are three classes of devices, Class I, II, and III. Class III devices include devices

that are life-supporting or life-sustaining, and devices that present a high or potentially unreasonable risk of illness or injury to the patient.

I feel like I can’t just sit back and watch this happen without asking if there is anything more we can do. . . . As an

M.D. with an interest in science, it seems to me that such

an approval would be akin to approving an experimental

product and is this what the FDA does? 60

Committee Staff interviewed the CDRH Director in April 2005

and asked questions relating to his decision to issue an approvable

letter to the sponsor in February 2005 despite the recommendations of the review team and the management staff at the branch,

division, and office levels of CDRH. According to FDA regulations,

as explained to Committee Staff by members of the review team,

an approval letter signed by the CDRH Director would reverse the

ODE’s August 11, 2004, not approvable decision. Therefore, if the

CDRH Director approved the device for TRD, he would be required

to document his rationale for approving the device in an internal

override memorandum.61 At the time of the interview, the CDRH

Director informed Committee Staff that he had not made his decision regarding approval of the device, and therefore, had not yet

drafted the override memorandum.

On July 15, 2005, the FDA approved the VNS Therapy System

for use in TRD patients. By signing the approval letter, the CDRH

Director overruled the comprehensive scientific evaluation of FDA

review team for the sponsor’s PMA-S, including more than 20 FDA

scientists, medical officers and management staff. According to the

CDRH Director’s override memorandum dated June 12, 2005, he

found the additional long-term data from the D–01 and D–02 studies that the sponsor submitted as an amendment to its PMA-S

(Amendment) to be compelling support for approval of the device,

contrary to the review team’s conclusions regarding that data.

B. FDA’s Public Materials Do Not Reveal the Extent of Scientific

Dissent Regarding Effectiveness of the Device

The Summary of Safety and Effectiveness (Summary), which is

posted on the FDA’s website, is silent with respect to the level of

scientific dissent within CDRH regarding the safety and effectiveness of the VNS Therapy System for TRD. It simply states that

CDRH believes that the sponsor ‘‘has provided reasonable assurance of safety and effectiveness based on valid scientific evidence

as required by statute and regulation for the approval of a Class

III medical device.’’ 62 However, throughout the review of the sponsor’s PMA-S, the review team recommended to the CDRH Director

that the device not be approved for TRD. Yet, at every stage of the

review, the team was instructed by the CDRH Director to proceed

with the next stage of pre-market review.

18

63 Although the panel recommended approval with conditions, one panel member stated in an

e-mail to the Executive Secretary of the Neurological Devices Panel dated June 18, 2004, ‘‘If

I were to have voted up front, I would have not approved the device.’’ Another panel member

said in an e-mail dated October 19, 2004, that she was not surprised that the FDA issued a

not approvable letter despite the panel’s recommendation. She stated, ‘‘This was not surprising

in and of itself, given the less than impressive nature of the data as well as the extreme ambivalence about the approval as reflected in the deliberations of the panel. I certainly was very ambivalent myself.’’ One of the two members who did not believe VNS Therapy should be approved

stated in an e-mail to a supervisory medical officer in CDER dated June 17, 2004, that ‘‘The

sponsor did not present convincing data that the treatment was effective, nor in my mind, that

it was safe.’’ See Appendix F. 64 According to several members of the review team, the panel’s recommendation was inconsistent with its discussion of the data on the risks and benefits of VNS Therapy. In particular,

even though the panel members found that without a randomized, controlled study they could

not determine how much of the response to VNS stimulation was due to a placebo effect or what

impact concomitant medications and ECT had on interpreting the efficacy of the VNS Therapy

System for TRD patients—two of the concerns that led the review team to recommend non-approval of the device—the majority of the panel members still concluded that the data provided

a reasonable assurance of effectiveness. See Neurological Devices Panel Meeting Transcript, p.

343–357, 363–368, http://www.fda.gov/ohrms/dockets/ac/04/transcripts/2004-4047t1.DOC.

The BlueCross BlueShield Technology Evaluation Center’s evaluation of the evidence on the effectiveness of VNS for TRD also noted that ‘‘Although the FDA voted to approve VNS Therapy,

a poll of committee members showed that approval was based on the safety of VNS Therapy

rather than strong evidence of efficacy.’’ In addition, the Executive Secretary of the June 15,

2005, panel informed Committee Staff that the June 15 meeting was ‘‘very unusual, emotional,

not data driven,’’ compared to more than a dozen panel meetings for which she was the executive secretary.

The Summary also presents a single conclusion from CDRH regarding the June 15, 2004, advisory panel’s recommendation. It

states that CDRH ‘‘concurred with the Panel’s recommendation of

June 15, 2004, and issued a letter to the sponsor on February 2,

2005, advising that its PMA was approvable subject to’’ specified

conditions. However, CDRH did not initially concur with the Panel’s recommendation of an approvable decision. A not approvable

letter was issued by the FDA on August 11, 2004. FDA staff who

were interviewed by Committee Staff explained that although the

panel recommended approval with conditions, the review team considered the panel’s discussion and deliberations as well as its recommendations in deciding whether or not the VNS Therapy System

should be approved for use in TRD patients.63 Based on the comments of the panel members 64 and the review team’s evaluation of

the PMA-S, the review team concluded that the data submitted by

the sponsor with its PMA-S did not meet the standard of reasonable assurance of safety and effectiveness.

Several FDA management staff, including the CDRH Director,

stated in interviews with Committee Staff that the CDRH Director

is very rarely directly involved in the approval or non-approval of

medical devices. They could recall only one other instance where

the Center Director made the final decision regarding a device’s approvability in the past decade. In that instance, the Center Director

decided not to reverse the Office Director’s decision. In the case of

the VNS Therapy System, the FDA review team that evaluated the

VNS Therapy System for TRD strongly disagreed with the CDRH

Director’s decision to approve that device, but despite the team’s

conclusions about the device, the CDRH Director decided independently to approve the VNS Therapy System for TRD.

Prior to Cyberonics’s PMA-S submission on October 27, 2003,

CDRH had expressed concerns about Cyberonics’s acute D–02 data;

however, the Center accepted the sponsor’s application for review.

According to an e-mail communication from CDER staff to CDRH

staff, dated October 3, 2003, if a sponsor had submitted to CDER

19

65The vehicle through which drug manufacturers seek the FDA’s approval of a new drug for

sale and marketing in the U.S. 66See Appendix F. 67 Ibid. 68 According to an e-mail dated February 4, 2004, from a review team member to the team

leader and Branch Chief, ‘‘Cyberonics spent an hour telling why it was completely impossible

for them to do a placebo controlled long-term (or short-term) study . . . but then, completely

out of the blue, promised that if we approved the device that they would do such a study post

approval. I find this offer extremely puzzling since their argument centered around troubles

with ethics, IRB cooperation, and patient recruitment. These are definitely not problems that

would go away post approval.’’ See Appendix F.

the type of data that Cyberonics’s did for FDA review and approval

of a drug, CDER would not have filed that sponsor’s application.

In that e-mail, the psychopharmacology expert in CDER who reviewed initial materials from the sponsor wrote:

I am concerned that we are not getting our point across

that the VNS for depression package that we reviewed represents a failed development program on face and that we

would not file this as an NDA [New Drug Application 65]

if it were a drug. We realize that you may have a different

threshold for approval when it comes to devices because of

the nature of the different diseases on which our respective Divisions are asked to comment. However, we tend to

view treatments for depression based on the disease and

not on the therapeutic modality (psychotherapy, drug, ECT

and now VNS). So it is artificial to us to consider one

study for a device (that is negative on face) as sufficient

to provide evidence for regulatory efficacy when we require

positive studies for a drug.66

The CDER expert added that:

The long term claims [of efficacy by the sponsor] are based

on open-label data. We do not allow labeling claims based

[on] open label studies that rely on historical controls in

depression. Historical controls in depression are extremely

unreliable.67

The FDA review team leader informed Committee Staff that the

team was puzzled by the CDRH Director’s decisions to proceed with

each stage of the review of the sponsor’s PMA-S despite the team

continuously recommending that the FDA not approve the VNS

Therapy System for TRD. According to the team leader and

DGRND Director, the team recommended non-approval prior to the

100-day meeting, because the team did not believe the sponsor

would be able to address the limitations of the clinical data provided in the PMA-S. The team leader and DGRND Director explained that the review team believed that the device could not be

approved without the sponsor conducting a new randomized, controlled study to demonstrate effectiveness. Throughout the review

of the sponsor’s PMA-S, DGRND recommended to the sponsor that

it conduct such a study prior to approval. However, the sponsor insisted each time that it was unnecessary and unethical to conduct

such a study, at least not before FDA approval of the device.68

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69 Even before the sponsor submitted its PMA-S in October 2003, the DGRND Director had

expressed concerns about the sponsor being able to demonstrate effectiveness after the failure

of the sponsor’s D–02 acute phase to show a difference in responses between those receiving

VNS Therapy and those who were not. According to minutes from a meeting between the sponsor and the FDA on March 1, 2002, the DGRND Director stated that she was not convinced

that the sponsor would not need a randomized, long-term study to demonstrate effectiveness.

About two weeks prior to the sponsor’s submission of the PMA-S, the FDA reiterated concerns

about the data limitations during a conference call with the sponsor. See October 11, 2002, conference call minutes. See Appendix H for the March and October 2002 minutes.

The team leader and DGRND Director acknowledged that randomized, controlled studies are not always required for FDA approval of devices, but the review team believed in the case of the

VNS Therapy System, a randomized, controlled trial was necessary

in order to distinguish improvement that is attributable to VNS

Therapy from improvement that is attributable to other reasons,

specifically, a placebo response or antidepressant treatments taken

concurrently with VNS Therapy.69 Nevertheless, Committee Staff

were told that the CDRH Director, who was the ODE Director at

the time, instructed the team to issue a major deficiency letter instead of a not approvable letter. The team leader said that the review team was surprised that the then-ODE Director would suggest a major deficiency letter without examining the sponsor’s data.

The CDRH Director, however, told Committee Staff that he asked

for a deficiency letter because he prefers giving sponsors ‘‘a second

bite at the apple,’’ to address concerns.

The team leader and DGRND director stated that, after reviewing the sponsor’s response to the major deficiency letter, the review

team concluded that the sponsor had not addressed all of the deficiencies in its PMA-S and could not do so without conducting a new

study. Consequently, the review team recommended that the device

not be approved. Once again, the team was told to proceed with an

advisory panel meeting to obtain recommendations on whether or

not the FDA should approve the device. The DGRND Director told

Committee Staff that she expressed her concerns to the then-ODE

Director about convening an advisory panel, asking him what the

FDA would do if the panel recommended approval despite the lack

of sufficient effectiveness data, which is what occurred at the panel

meeting. The then-ODE Director told Committee Staff that if the

panel had agreed with the review team’s assessment of the sponsor’s clinical data, the panel’s recommendation would provide additional support for a not approvable decision.

According to the ODE Deputy Clinical Director, soon after the

June 15, 2004, advisory panel meeting, the ODE Director asked

him to review the sponsor’s application to advise her on whether

or not the office should approve the VNS Therapy System for TRD.

The Deputy Clinical Director informed Committee Staff that he

was not initially involved in the review of the sponsor’s PMA-S. He

reviewed the transcript of the advisory panel meeting, the PMA-S

file, and the review team’s memoranda and supported DGRND’s

recommendation to not approve the device for TRD. In addition,

after the not approvable letter was issued on August 11, 2004, the

Deputy Clinical Director requested and reviewed additional patient

response data from the sponsor and concluded in an e-mail to the

ODE Director dated September 14, 2004:

21

70See Appendix F. 71 According to the CDRH Director, DGRND’s interactions with the sponsor were ‘‘terrible’’

and the staff felt ‘‘abused’’ in meetings with the sponsor. The ODE Director informed Committee

Staff that she spoke with the Chief Executive Officer of Cyberonics at the end of a meeting and

requested that he refrain from yelling at her review team. 72See Appendix F.

I do not see anything in the information which would convincingly make me decide to overrule the original Division/

Office decision.70

Committee Staff were informed that the team leader as well as

the DGRND, ODE, and CDRH Directors received hundreds of letters and phone calls opposing the FDA’s August 11, 2004, decision

to not approve the device for treatment-resistant depression. FDA

staff interviewed by Committee Staff stated that interactions with

the sponsor were not collegial 71 and the company was more aggressive than other sponsors in pursuing FDA approval. According to

the CDRH Director and Ombudsman, the sponsor also spoke with

staff in the Office of the Secretary, Department of Health and

Human Services, who in turn followed up with CDRH regarding

the FDA’s not approvable letter. As a result of the influx of letters

and phone calls after the not approvable letter was issued, the

CDRH Director informed Committee Staff that he kept then-FDA

Commissioner Lester Crawford apprised of developments in the review of the sponsor’s PMA-S during his bi-weekly meetings with

the Commissioner.

On September 23, 2004, the sponsor submitted its Amendment,

in response to the not approvable letter. The review team examined

the data and information provided in the sponsor’s Amendment

submission and, on November 10, 2004, concluded that the not approvable decision should stand. However, according to the review

team leader and the DGRND and ODE Directors, the CDRH Director decided to schedule a meeting with the sponsor in December

2004 to further discuss the sponsor’s Amendment and what the

sponsor could do to enable the FDA to reach approval of the VNS

Therapy System for TRD. Only four members of the review team

were invited to attend the meeting, and according to the team leader and DGRND Director, management staff were not invited to

participate in the meeting.

When the Restorative Devices Branch Chief learned that the

CDRH Director planned to hold a meeting with the sponsor that

would not include the management staff involved in the sponsor’s

PMA-S review—the branch chief, the deputy division director, and

the division director—he expressed his concerns to the team leader.

In an e-mail dated November 24, 2004, he wrote:

Don’t know if you heard yesterday, but [the CDRH Director] has made a decision—of sorts. His plan is to have a

meeting with the sponsor and the partial review team, for

us to explain again why we came out to a different conclusion with the same data. I’ll be meeting with [the ODE Director] today, and explain why I think that’s a really bad

idea, but chances are that’s what’ll happen.72

The CDRH Director stated to Committee Staff during his interview that the management staff were not intentionally excluded.

22

73See Appendix F.

However, only the team leader and three other members of the review team were invited—a medical officer, the CDER psychopharmacology expert, and the ODE Deputy Clinical Director. The

review team leader informed Committee Staff during an interview

that he felt ‘‘outnumbered’’ by the sponsor’s representatives. In addition, he wrote in his e-mail response to the Branch Chief dated

November 29, 2004, that he was very troubled about the decision

to hold a meeting without management and said such a meeting

seemed ‘‘highly irregular.’’ See Appendix F.

The CDER psychopharmacology expert on the review team also

expressed his concern regarding the December 2004 meeting when

he was told to limit his comments to the sponsor’s clinical data and

not discuss what types of studies CDER or the Center for Biologics

Evaluation and Research would require for approval. He stated in

an e-mail dated November 24, 2004:

I am a little troubled by what appears to be a request that

I not discuss the need for replicated controlled data in our

upcoming discussion with Cyberonics and [the CDRH Director]. I am left with the impression that you may view

our Division’s opinion on the need for replicated controlled

trial data as simply a bureaucratic policy difference between Centers. . . . This need for replicated controlled clinical trial data is a basic tenet of psychiatric clinical research. This need is based on sad experience. I suggest

that the need for two randomized controlled trials should

actually be the focus of this upcoming meeting.73

According to the CDRH Director and the Deputy Commissioner

for Operations, the CDRH Director sought the Deputy Commissioner’s advice on how to proceed with the review of the VNS Therapy System for TRD because of the Deputy Commissioner’s expertise on antidepressants. During an interview with Committee Staff,

the CDRH Director stated that he and the Deputy Commissioner

discussed ways to obtain more data on the device, such as requesting the sponsor to conduct additional studies pre- or post-approval;

however, the Deputy Commissioner did not advise him to approve

or not approve the device. When he asked her impression of the

sponsor’s VNS Therapy for TRD, he said she was ‘‘lukewarm’’ about

the device. According to the CDRH Director, the Deputy Commissioner said there could be something there, but the studies were

flawed.

The Deputy Commissioner also informed Committee Staff that

she spoke with the Director of the Office of Medical Policy regarding potential studies that the sponsor could conduct to generate

more effectiveness data on its device. She suggested to the CDRH

Director a ‘‘randomized withdrawal’’ study, i.e., randomly withdrawing VNS treatment from D–02 patients that the sponsor labeled as ‘‘responders.’’ According to the Deputy Commissioner, if

the device works, the sponsor should observe a relapse in patients

when their treatment is withdrawn. Alternatively, because patients

usually can tell if the device is on, she suggested randomly reducing the output of the stimulator rather then fully withdrawing

23

74See Appendix F. 75 By letter dated July 7, 2005, Chairman Grassley and Ranking Member Baucus asked the

FDA whether or not an agreement or understanding was reached between the sponsor and the

FDA regarding FDA approval of VNS Therapy for TRD if the sponsor agreed to voluntarily withdraw VNS Therapy for TRD should post-marketing studies fail to show efficacy. The FDA provided its response on July 20, 2005. See Appendix E. In that response, the FDA noted that ‘‘consideration of post-market controls is an important component of FDA’s Pre-Market Approval

program for devices.’’ The FDA also stated that ‘‘there exists no agreement or understanding

between FDA and Cyberonics, written or oral,’’ and ‘‘such an agreement or understanding between FDA and Cyberonics has never been discussed.’’ However, given the FDA’s post-market

authorities, ‘‘studies agreed to by Cyberonics do not reflect an inappropriate agreement by the

Agency to permit the marketing of a device in exchange for a promise of withdrawal should the

studies show the device to be ineffective.’’ 76See Appendix E.

treatment. By e-mail dated December 23, 2004, the Director of the

Office of Medical Policy also suggested to the CDRH Director a

study that the sponsor ‘‘can and should do,’’ a randomized withdrawal study.74 However, he questioned whether or not the sponsor

could ‘‘realistically’’ conduct such a study post-approval.75 The Deputy Commissioner informed Committee Staff that the FDA received

‘‘push back’’ from the sponsor on the proposal.

On July 28, 2005, the Chairman and Ranking Member sent a letter to the FDA to question why the FDA’s website did not address

the level of scientific dissent within CDRH regarding the review

and approval of the VNS Therapy System for TRD. FDA’s response,

dated August 9, 2005, states:

The absence from the SSE of any discussion of internal

discussions and the decision-making process that led to the

approval reflects the policy of the Agency not to disclose

pre-decisional and deliberative process information. . . .

The reasons for this policy are to encourage open and

frank discussions among colleagues and between subordinates and superiors at FDA and to protect against public

confusion that might result from disclosure of reasons and

rationales that were not in fact ultimately the grounds for

the Agency’s decision.76

A review of whether or not the FDA uniformly adheres to this

policy, however, shows that enforcement of the policy appears to

depend on the interests of FDA management rather than any stated interest in encouraging scientific debate or in protecting the

public. The Committee Staff are aware of more than one instance

in recent years where the FDA has forthrightly publicized internal

dissent regarding safety and effectiveness.

While Committee Staff recognize that it is not uncommon for

FDA reviewers to disagree about the findings and conclusions regarding the safety and/or effectiveness of a drug or device, the level

of dissent regarding the approval of the VNS Therapy System for

TRD goes far beyond that of ‘‘open and frank discussions.’’ As the

CDRH Director acknowledged to Committee Staff prior to his decision to approve the device, if he approved the device, the public

would not be aware of his decision to overrule more than 20 FDA

staff.

24

77See Appendix A. 78 A ‘‘sham’’ is used to resemble a treatment without actual use of the treatment. A placebo

is an example of a sham control. 79See Appendix B.

C. Not All Relevant Findings and Conclusions Regarding Safety

and Effectiveness of the Device Were Made Publicly Available

Through its website, the FDA has made available to the public

the approval letter for the VNS Therapy System for TRD, the Summary of Safety and Effectiveness (Summary), physician and patient

labeling information for the device, and other information for consumers. The Committee Staff reviewed these materials as well as

other information and documents obtained by and provided to the

Committee from the FDA and the sponsor. Based on that review,

the Chairman and Ranking Member questioned, by letter dated

July 28, 2005, the FDA’s decision not to disclose certain information regarding the effectiveness of the VNS Therapy System that

appears relevant to those who are considering having this device

implanted.77

In the July 28, 2005, letter, the Chairman and Ranking Member

noted that during an interview conducted with the CDRH Director,

prior to approval of the VNS Therapy System for TRD, the Director

acknowledged that data from the only randomized, controlled

study, the acute phase of D–02, failed to demonstrate the effectiveness of the VNS Therapy System for TRD. The Director’s internal

override memorandum dated June 12, 2005, states:

With regard to effectiveness, I think it needs to be stated

clearly and unambiguously that the short-term randomized

comparison of VNS active to VNS sham 78 at 12 weeks

failed to reach, or even come close to reaching, statistical

significance with respect to its primary endpoint. I think

that one has to conclude that, based on that data; either

the device has no effect, or, if it does have an effect that

in order to measure that effect a longer period of followup is required.79

However, the Director’s comments regarding the effectiveness of

the VNS Therapy System for TRD are absent from the Summary

that is posted on the FDA’s website. The Chairman and Ranking

Member also noted in the July 28, 2005 letter to the FDA that the

patient labeling of the VNS Therapy System for TRD does not

make clear the Director’s own conclusions regarding the sponsor’s

short-term clinical study. Instead of stating ‘‘clearly and unambiguously’’ that the ‘‘[VNS Therapy System for TRD] has no effect, or,

if it does have an effect that in order to measure that effect a

longer period of follow-up is required,’’ the patient labeling for the

VNS Therapy System for TRD states:

At the end of the first 3 months, the proportion of patients

who had at least a 50 percent reduction in depression

symptoms was 15 percent in the group of patients receiving active stimulation, slightly better than for patients

who were not receiving stimulation (10 percent of these patients had at least a 50 percent reduction in symptoms).

25

80See Appendix D. 81See Appendix E. 82See Appendix B.

. . . This finding suggested that the full effects of VNS

Therapy might require more than 3 months of treatment.80

On August 9, 2005, the FDA responded to the Committee and

cited a different section of the patient labeling to show that the labeling acknowledges ‘‘the failure of the data to demonstrate shortterm effectiveness.’’81 The labeling states that ‘‘the 12 week acute

studies did not show a significant difference between patients receiving VNS Therapy and those not receiving it.’’ However, it does

not explain that ‘‘did not show a significant difference’’ means that

any differences observed between the two groups of patients could

have been due to chance rather than a response to the device. Because it could not be determined if the effect of the device was real

or due to chance, the CDRH Director concluded in his override

memorandum that, based on the results of the short-term study, a

longer study would be needed to determine whether or not the device is effective.

In response to the Chairman and Ranking Member, the FDA also

stated that it would review the CDRH Consumer Information

webpage (www.fda.gov/cdrh/mda/docs/p970003s050.html) regarding the approval of the VNS Therapy System for TRD to determine

whether or not it could be revised to provide more helpful information to patients. By e-mail dated August 23, 2005, the FDA notified

Committee Staff that it had revised its webpage. The current

webpage, updated on August 12, 2005, includes additional information on when the device can be used:

The device is to be used only in patients 18 years of age

or over with treatment-resistant depression (TRD). These

are patients who have been treated with, but failed to respond to, at least 4 adequate medication and/or ECT treatment regimens prescribed by their physician. It is not intended to be used as a first-line treatment, even for patients with severe depression.82

The FDA also added information regarding what the VNS Therapy System is intended to accomplish. Specifically, the CDRH Consumer Information webpage on VNS Therapy states:

Based on the results of a clinical study of over 200 patients

conducted in the United States, during the first 3 months

of therapy, patients who had the device implanted and

turned on did not show any significant advantage in response compared to patients in whom the device was implanted but not turned on.

The additional information regarding the short-term effectiveness

data is similar to what is provided in the patient labeling. However, as presented, the information does not represent the gravity

of the statement made by the CDRH Director in his override

memorandum that the short-term study ‘‘failed to reach, or even

come close to reaching, statistical significance with respect to its

primary endpoint [of efficacy].’’ Nor does it represent the conclusions of the review team or the management staff at the branch,

26

83Final review memorandum, see Appendix D, p. 207. 84 ‘‘Requirements on Content and Format of Labeling for Human Prescription Drug and Biological Products,’’ 71 Fed. Reg. 3922, 3969. (January 24, 2006).

division and office levels who found the sponsor’s data on the effectiveness of the VNS Therapy System for TRD to be ‘‘weak’’ and insufficient for FDA approval of the device.

In addition, because the review team’s own assessment of the

safety and effectiveness of the device is not available to the public,

patients and physicians are not made aware of the reviewers’ concerns regarding the safety of the VNS Therapy System for TRD in

light of the team’s conclusion that the device has not been shown

to be effective. The review team stated in its final review memorandum dated January 6, 2005, ‘‘any safety risk associated with

using a long-term implant, in the absence of a reasonable assurance of effectiveness data, is excessive.’’ 83 The FDA review team

also believed that the sponsor did not provide a reasonable assurance of safety because the safety data provided in the PMA-S did

not allow an accurate assessment of any increased risks of using

the device for TRD.

In the Preamble to a final rule on drug and biological products

labeling, the FDA recently stated:

The centerpiece of risk management for prescription drugs

generally is the labeling, which reflects thorough FDA review of the pertinent scientific evidence and communicates

to health care practitioners the agency’s formal, authoritative conclusions regarding the conditions under which

the product can be used safely and effectively in accordance with the act. . . .

As FDA has long recognized, its role is not to regulate

medical practice. The agency’s actions nevertheless affect

medical practice in a variety of ways. For example, FDA

approval decisions affect the availability of drugs and medical devices. Also, FDA decisions as to the content and format of prescription drug labeling affect health care practitioner communications with patients, to the extent such labeling is relied upon by such practitioners to guide their

discussions of risk with patients. FDA strongly believes

that health care practitioners should be able to rely on

prescription drug labeling for authoritative risk information and that health care practitioners should not be required to convey risk information to patients that is not included in the labeling.84

While these statements were made with respect to labeling for

drug and biological products, they have implications for how and

what information might be conveyed in device labeling. The FDA’s

position is that health care providers and their patients should be

relying on the FDA for ‘‘authoritative risk information.’’ However,

the questionable aspects of the agency’s regulatory approval process as evidenced in this Report suggest that health care providers

relying on the FDA’s authoritative information may not be able to

convey complete risk information to their patients on the safety

and effectiveness of the VNS Therapy System, because not all of

27

the relevant findings and conclusions regarding this device have

been made available.

Then-FDA Commissioner Crawford testified on July 26, 2005, before the House of Representatives Committee on Appropriations

Subcommittee on Agriculture, Rural Development, Food and Drug

Administration, and Related Agencies that he would make the FDA

‘‘a much more open and transparent organization.’’ This pledge has

been reiterated by the FDA in letters to the Committee on other

matters. However, selective disclosure of the FDA’s findings and

conclusions regarding the safety and effectiveness of a device, in

this case the VNS Therapy System for TRD, appears inconsistent

with that pledge.

VI. Concluding Observations

The public relies on the FDA to weigh the risks and benefits of

a new medical device or a new indication for a device to determine

whether or not the device is reasonably safe and effective for use.

FDA approval has long been considered the gold standard. However, the events and circumstances surrounding the FDA’s review

and approval of the VNS Therapy System for TRD—including the

rare involvement of the CDRH Director and other high level FDA

officials in the review of a device; the insistence of a single official

to continue review of the PMA-S despite the repeated recommendations of over 20 FDA scientists, medical officers, and management

staff to not approve the device throughout approximately 15

months of review; a ‘‘highly irregular’’ meeting between the sponsor

and the FDA; and external pressure from the sponsor as well as

hundreds of health care providers and TRD patients through letters, e-mails and phone calls—raise legitimate questions about the

FDA’s decision to approve that device for the treatment of TRD. In

light of the significant scientific dissent within the FDA regarding

the effectiveness of the VNS Therapy System for TRD and the conclusion not only of the review team for the sponsor’s PMA-S but

also of high level officials in the FDA that the effectiveness data

were weak, concerns persist that the FDA’s standard of reasonable

assurance of effectiveness may not have been met.

The FDA has standards for approval that must be met so that

there is some assurance that the products approved for commercial

distribution are safe and effective when used as directed in the

product labeling. As a result of the short lifespan of new devices,

different standards for demonstrating effectiveness may apply for

devices compared to drugs. An approved device can quickly be replaced by a newer model or by smaller, better, and more sophisticated devices. However, what remains the same in FDA’s approval

of a device or a drug is the requirement that data supporting a

sponsor’s application for approval be scientifically sound. Otherwise

health care providers and insurers as well as patients may question the integrity and reliability of the FDA’s assessment of the

safety and effectiveness of an approved product. In the case of VNS

Therapy for TRD, the FDA review team for the sponsor’s PMA-S

believed that conducting a new randomized, controlled study would

be the only way that the sponsor could address the data limitations

in its PMA-S and repeatedly recommended that the sponsor conVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00035 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
28

duct the study prior to approval. However, the sponsor refused to

conduct another randomized, controlled study pre-approval.

FDA approval does not mean that a device is risk-free or that it

will work in every patient. The determination of a medical device’s

safety and effectiveness prior to approval is based largely on studies that are conducted in small populations. While valuable information about the effectiveness of a device can be gained and new

risks are sometimes identified once the device is on the market and

used by millions of people, the FDA should not be making devices

available to the public if those devices have not reached the agency’s standard for safety and effectiveness. With respect to the VNS

Therapy System for TRD, however, it appears that instead of relying on the comprehensive scientific evaluation of its scientists and

medical officers, the FDA lowered its threshold for evidence of effectiveness. The FDA approved the VNS Therapy System for TRD

based on what its own reviewers considered to be weak data and

allowed the sponsor to test its device post-approval, contrary to the

recommendations of the review team.

In addition to questions about the effectiveness of VNS Therapy

System in the population for which the device is intended, concerns

exist about the potential off-label uses of the device. Because the

FDA does not regulate the practice of medicine, once a device is on

the market, it is available for widespread use. While there have

been benefits derived from off-label uses, the safety and effectiveness of off-label uses are not known and therefore can pose serious

health risks to patients. The circumstances are no different for the

VNS Therapy System for TRD. The specific public safety concern

related to off-label use of this device is the implantation of the device in children with TRD. For example, the VNS Therapy System

for epilepsy is approved only for use in patients 12 years of age or

older, but off-label use of the device has occurred in children as

young as five years of age. There are risks with using the VNS

Therapy System in children that do not exist among adults because

implantation of the device involves wrapping a wire around the

nerve of a growing child. In the case of TRD, the VNS Therapy System is approved only for patients 18 years of age or older.

The level of scientific dissent within the FDA regarding the effectiveness of the VNS Therapy System for TRD also raises concerns

about the use of taxpayer dollars to pay for a $25,000 device, including implantation and programming, that over 20 FDA scientists, medical officers, and management staff believed should not

be approved for the treatment of TRD. Whether or not a device is

effective is not only a major public safety concern, but also a very

important financial concern. The Medicare and Medicaid programs

pay for health care services received by millions of Americans, so

the Committee has a responsibility to ensure that the programs

pay for medical devices approved based not on an abstract estimation of safety and effectiveness but on a comprehensive scientific

evaluation of the product’s benefits and risks, in accordance with

all laws and regulations.

In addition, patients and their doctors, including Medicare and

Medicaid beneficiaries, should have access to all relevant findings

and conclusions regarding the safety and effectiveness of a device.

The CDRH Director acknowledged during a media briefing on FebVerDate 11-MAY-2000 09:43 Feb 16, 2006 Jkt 095484 PO 00000 Frm 00036 Fmt 6633 Sfmt 6633 24711.XXX SFINANC2 PsN: SFINANC2
29

ruary 2, 2006 that one of the FDA’s ‘‘biggest challenges is in terms

of providing useful information, and we understand that a lot of

the concerns that have been raised over the course of the last few

months to a year is with regard to the information that we

present—the quantity of information and the timeliness of that information.’’ Concerns remain about the lack of transparency regarding the approval process for the VNS Therapy System, which

deprives doctors and their patients of information that may be relevant to a patient’s care. All relevant findings and conclusions regarding the safety and effectiveness of the VNS Therapy System

for TRD should be made available to patients and their doctors to

enable them to make fully informed health care decisions and ensure all risks and benefits can be carefully weighed by those considering having the device implanted.

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(33)

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APPENDIX A—CHAIRMAN AND RANKING MEMBER

LETTERS TO THE FDA

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APPENDIX B—APPROVAL AND LABELING INFORMATION

POSTED ON FDA’S WEBSITE

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APPENDIX C—FDA REGULATIONS

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APPENDIX D—INTERNAL FDA MEMORANDA

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APPENDIX E—FDA LETTERS

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APPENDIX F—E-MAIL COMMUNICATIONS AND

OTHER FDA DOCUMENTS

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APPENDIX G—NEUROLOGICAL DEVICES PANEL MEETING

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APPENDIX H—MINUTES

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APPENDIX I—FDA ADVICE/GUIDANCE DOCUMENTS

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APPENDIX J—TECHNOLOGY EVALUATION CENTER, BLUE CROSS AND

BLUE SHIELD ASSOCIATION

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APPENDIX K—CDRH ORGANIZATIONAL CHART

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