I certify that I
was at the June 12, 2004, Joint Meeting of the Dermatologic and
Ophthalmic Drugs Advisory Committee (DODAC) and the Drug Safety and Risk
Management Advisory Committee (DSaRM) and these minutes accurately reflect the
discussions of the committee.
_________//S//____________________ _________//S//________________
Robert S. Stern,
M.D., Kimberly Littleton
Topper, M.S.
Chairman, DODAC Executive
Secretary, DODAC
Joint
Meeting of the
Dermatologic
and Ophthalmic Drugs Advisory Committee (DODAC)
and the
Drug
Safety and Risk Management Advisory Committee (DSaRM)
July 12, 2004
Minutes
The
meeting was called to order at 8:00 by Dr. Robert Stern. He welcomed everyone and had the head table
introduce themselves. The conflict of
interest statement was read into the record by Kimberly L. Topper. Dr Jonca Bull welcomed everyone and
thanked the committee for assisting the FDA in their deliberations. She
reminded the committee of the February 04 discussions on fetal exposure and the
proposed Risk Management Plan (RMP) Dr. Jonathan Wilkin also thanked the committee
and set the stage for discussions on (NDA) 21-701, proposed trade name Tazoral
(oral tazarotene 1.5mg and 4.5 mg) capsules, Allergan, Inc., proposed for the
treatment of moderate to severe psoriasis, including risk management options to
prevent fetal exposure. He reminded the
committee that no product is perfect and finding the balance for the risk
benefit ratio is what they need to look for during the day's discussions.
Denise Cook, M.D., FDA, provided an "Introduction
to Psoriasis & The State of the Armamentarium." She discussed the prevalence, the genetics
and pathogenesis, and the clinical variants of psoriasis. She presented the current treatments
available and the side effects and contraindications of each.
Allergan NDA Presentation
Patricia Walker, M.D., Ph.D., Vice President, Skin Care
Pharmaceuticals, Allergan, Inc. introduced Tazarotene Capsules
in the treatment of psoriasis. She
reminded the committee that Allergan is seeking the approval of Tazarotene for
the treatment of moderate to very severe plaque psoriasis. She discussed the regulatory history of
Tazarotene and provided a list of the members that were available to answer the
committee questions.
Alan Menter, M.D., Clinical Professor of Dermatology, University of Texas, Southwestern, presented on Psoriasis:
Disease Overview and Treatment Options.
He stated the opportunities to improve care exist and that psoriasis is
a diverse disease and no one drug is suitable for all patients. Current treatments have therapeutic
limitations and a full range of safe, efficacious and accessible medications
are needed for the psoriatic population.
Patricia Walker, M.D., Ph.D. presented the pharmacology of
Tazarotene. Tazarotene is a prodrug
with only one active metabolite, tazarotenic acid. It is an acetylenic retinoid and has a locked
molecule. She then covered the efficacy
data for Tazarotene. The safety and efficacy
of oral tazarotene is based on the results of 12 phase 1 studies in normal
volunteers, 1 dose ranging study in patients with moderate to very severe
plaque psoriasis and 4 phase 3 studies in patients with moderate to very severe
plaque psoriasis. The Overall Lesional
Assessment (OLA) was an integrated clinical assessment of overall psoriasis
severity and it evaluates the signs of psoriasis on a 6 point scale (none,
minimal, mild, moderate, severe and very severe). A photo numeric guideline was provided for
clinical evaluation. She provided
examples of clinical response and the demographic breakdown of the clinical
trials. The efficacy summary showed that
`20% of patients achieved no or minimal disease, moderate (>50%) to complete
clearing was achieved in the majority of patients, significant improvements in
plaque elevation, erythema, scaling, purities, and % body surface area (BSA),
maintenance of benefit was observed following discontinuation of drug, there
was no rebounding and a large portion of patients (79%) expressed treatment
satisfaction. She ten discussed the
clinical development safety data. The
bone mineral density (BMD) changes were small with individuals with gains or
losses of >5% within expected variation and they were not associated
with fractures, osteoporosis, age, gender or systemic corticosteroids. She stated that they did not recommend
routine laboratory evaluations nor was routine bone monitoring necessary. She then explained the proposed RiskMap for
oral Tazarotene. She stated their goals
as 1) women who are pregnant shall not be prescribed or dispensed oral
tazarotene and 2) women taking oral tazarotene shall not become pregnant. The primary components of the RiskMap will be
mandatory registration for all patients, targeted education for all patients,
mandatory registration and certification of physicians and pharmacies,
verification of all patients qualified by pharmacist through interaction with
technology-based system, laboratory based pregnancy testing system, managed
access, pregnancy exposure registry, and program effective metrics.
Alan Menter, M.D. then discussed the Risk Benefit Assessment. He discussed the important differentiating
characteristics of oral tazarotene and the characteristic safety profile of systemic
retinoid drugs. He stated that the
half-life of the drug is very short; it can be taken when patient drinks
alcohol, there is neither change in the lipid metabolism nor a change in the hepatotoxicity
and the alopecia is not different after 12 weeks and the mucocutaneous
reactions are mostly mild. He concluded
that oral tazarotene is safe and effective and they have shown sustained
clinical benefit in patients with moderate to very severe plaque psoriasis;
ongoing therapy with tazarotene capsules provides extended benefit; there is a
high rate of patient acceptance and a low dropout rate due to adverse
events. He concluded that "Based
on the efficacy and safety profile, tazarotene capsules should be available as
an option for ALL patients, male and female, with moderate to very severe
plaque psoriasis." Allergan
then answered clarifying questions from the committee.
The
committee took a 15 minute break.
FDA Presentation
Jiaqin Yao, Ph.D., FDA, presented the "Toxicology
Studies of Tazarotene." He
discussed the toxicity in fertility and early embryonic development, prenatal
and postnatal development, male reproductive toxicity, the recommended human
dose and the lowest teratogenic dose. He
concluded that the human may be the most sensitive species for teratogenicity
of retinoids; tazarotene is a more potent Teratogen than other retinoids in
rats and rabbits on an mg/kg/day basis; and tazarotene is a probable human
teratogen.
Tapash
Ghosh, Ph.D. FDA, presented "Clinical
Pharmacology & Biopharmaceutics" covering pharmacokinetics of
Tazarotene (TAZ) and Tazarotenic acid (TA) in humans; the potential for
drug-drug interactions and the tazarotenic acid in semen. He concluded that the no-effect limit for
teratogenicity for TAZ/TA is unknown in humans; the fertilized egg may remain
exposed to TA in the semen following repeated sexual encounters; and the risk
to the fetus, if any, while a male patient is taking the drug or after it is
discontinued can not be ruled out.
Denise Cook, M.D., FDA, discussed the
clinical safety of oral tazarotene. She
covered the safety discontinuations, the adverse events that led to
discontinuation in the long term trial, the significant adverse events to
include the bone, metabolic and endocrine events, and the long term safety
trial. She concluded that for the
neuropsychiatric events there was no difference between tazarotene and placebo
in the controlled trials but due to the limitations of the metrics employed and
the statistical power an association cannot be ruled out, given the existing
concerns about other such effects from other retinoids. She
also stated that there was a mean bone mineral density (BMD) decrease over time
for the entire set of patients, with some having decreases close to 30%.
Shiowjen Lee, Ph.D., FDA, provided the "Biostatistical
Analysis of Pivotal Studies." She
stated that oral tazarotene is statistically superior to placebo regarding
treatment success although success rates are below 20% for both studies; female
patients had higher success rates than males though makes accounted for over
2/3 of study enrollment in each trial. Treatment success decreases as baseline OLA score increases and there
is insufficient data to evaluate the efficacy claim of "very severe"
plaque psoriasis. Oral tazarotene
demonstrates short term efficacy in treating scalp psoriasis but not in
treating nail psoriasis.
Denise Cook, M.D. then presented the
clinical wrap-up discussing the drug use trends, adverse events and the
efficacy of both oral and topical tazarotene.
Jill Lindstrom, M.D., FDA, spoke on the "Evolution
of Risk Management for Systemic Retinoids." She provided an overview of the background of
the retinoids currently approved for use by FDA, their historical development
of risk management for systemic retinoids and in summary she states that all
approved systemic retinoids are known or highly suspect potent human
teratogens, risk management plans should incorporate the current best practices
and current best practices for pregnancy prevention include, labeling, targeted
education, reminder systems and controlled distribution.
Ann Trontell, M.D., M.P.H. FDA, discussed the
"Potential Risk Management Tools for Oral Tazarotene: Context,
Considerations, and Experience."
She described the risk management in the context of the PDUFA3 Draft
Guidance's, discussed the advantages and disadvantages of different tools,
described the isotretinoin risk management for teratogenicity and placed the
options proposed by the sponsor for tazarotene into context. She summarized that the systemic retinoid
teratogenicity risk management plan for isotretinoin has evolved over time and
the tazarotene RiskMAP has proposals for a reminder system for females of child
bearing potential and a registry for physicians and pharmacists similar to that
of the S.M.A.R.T. system.
The
committee asked clarifying questions of the FDA presenters and then adjourned
at 12:05 for lunch.
The meeting resumed at 1:00. The Open Public Hearing (OPH) had 3 speakers
registered. Mr. White spoke about the National
Psoriasis Foundation, the impact of psoriasis, and his experience as a person
whose son has psoriasis. Ms. Janey Freeman spoke about her experience as a
person with psoriasis and about her positive experience with oral
tazarotene. Mr. Gorre spoke about his experience as a
person with psoriasis and about his positive experience with oral
tazarotene. The Chair asked for any
other speakers for the OPH and seeing none the OPH was closed at 1:25.
The committee continued the
discussion with both FDA and Allergan answering questions on a wide variety of
topics. At 2:52 the committee took a break and
returned at 3:00 to start answering the
questions.
1.
Based on the information from the clinical studies conducted for
tazarotene capsules, is there an adequate demonstration of effectiveness for
moderate to severe psoriasis?
· Efficacy was not shown at the end of the 12 week study
· It did show that it is more effective than placebo (6 members)
· The efficacy shown does not represent a significant benefit over what is
currently on the market
· The short half life could be a benefit with other types of psoriasis
· Do not know the reliability of the scoring tool therefore the extent of efficacy
is an issue
· The drugs short half life is compelling for patients at risk of becoming
pregnant and cannot reliably forgo pregnancy for a long post treatment as
required for oral retinoid approved for psoriasis
· Concern about off label use for acne given that the topical form is
widely used for this indication, posters and non peer reviewed publications
suggesting efficacy have been presented to dermatologists , and efficacy of
Tazoral including remission rate and duration relative to isotretinoin (and
hence risk/benefit ratio for a high risk drug) has not been established.
Is there an adequate demonstration of efficacy
for “very severe” psoriasis?
· There was not enough power (15 patients) to show efficacy
· It is difficult to show progress in 12 weeks
· It showed that it cleared some and the patient may be happy with that
but it did not meet the point required to pass
· There was no demonstration for efficacy for very severe psoriasis (5
members)
2.
Has the safety profile for this product been adequately assessed?
A)
Please provide discussion of the clinical and preclinical safety data,
including comments on bone and liver abnormalities, hyperlipidemia, and
teratogenicity.
· There is great concern about the pregnancy rate with the drug - there
needs to be better follow-up
· The study was inadequately powered to show safety and the demographics
of the subjects need to be improved (4 members)
· There was not enough information on the tendency to fracture with the
bone information
· Not overly concerned about hyperlipidemia as it can be treated but there
was not enough data to adequately assess the drugs effect
· The teratogenicity is a grave concern and a risk management plan must be
implemented
· The liver abnormalities were well explained in their presentation and
are controllable
B)
Please discuss any potential issues, regarding long term safety of oral
tazarotene with repeated use.
· Currently there is not enough long term safety data
· Need long term bone data and pregnancy data if the drug is going to be
used long term
· Need labeling to address lab abnormalities, liver function tests, and
alkaline phosphatase and require continuous monitoring
· Concern over the bone and pregnancy issues
3. Given the safety and efficacy information,
does the Committee find a favorable
balance of risks
and benefits which would support approval of this product?
· Yes - 3 Raimer, Schmidt, Wilkerson
§ With monitoring of Phase IV study
· No - 9 Knudson, Epps, Katz, Ringel, Stern, Gardner, Levin, Honein
§ There is too much unknown
§ Not enough data to power the studies
· Abstain - 4 Shapiro, Day, Furberg, Holmboe
§ Needs more data
§ information is missing
§ need to see an outline of a risk management plan to feel comfortable
approving
§ need Phase IV study information
4. Allergan
has submitted a risk minimization proposal to the NDA that is similar to the
isotretinoin SMART program. In addition,
they have described in their package to the advisory committee a registry
program that appears to be similar to the emerging isotretinoin risk
minimization program. Both programs
exempt males and females not of childbearing potential from many program
requirements, including refill restrictions.
A)
Please comment on which teratogenic risk management program is preferred
for tazarotene?
· Want consistent program across the board for all Retinoids / Teratogens
· Include in risk management plan how drugs are used - "Use
Data"
· Do not use marketing data - use actual "use data"
· Concern over "use data" on script due to insurance issues
· Want a consistent program but have enough flexibility to allow sponsors
to make changes
· Collect "use data" but be concerned over insurance companies
denial of coverage
· Involve patients to increase participation
· Have some form of a feedback loop to practitioners to help change
behaviors
B)
Please comment on the advantages and disadvantages of having
teratogenicity program requirements applied solely for Female Child Bearing
Potential.
· With males there is exposure at conception and continued exposure during
pregnancy if not followed
· A one size fits all Risk Management Program would need to follow
everyone male & female alike
· There is a current concern about the male semen therefore they should be
followed
· See comments for # 5
C)
Are the scientific and clinical uncertainties surrounding semen levels
of tazarotenic acid a factor to be considered in tazarotene risk minimization?
· It should be considered and more data gathered
· Comfortable with data presented
· Suggest condom use in labeling
5.)
How can FDA best address the potential clinical relevance of high
tazarotenic acid levels in semen?
Options might include:
· Concerns could be alleviated by labeling information discussing
restrictions
· This must be discussed in labeling
· Need to look at effect in subpopulations
· Animal studies needed to determine effect at dose target
A)
further delineation of the potential risks (via consultation
with teratogenicity experts, additional preclinical studies, etc.)
· More studies are needed (8 members)
· Need long term follow up for bone issues and efficacy rate
B)
informing clinicians and patients of the finding and its uncertain
clinical relevance
· Provide known information and allow the patient to make final judgment
(6 members)
C)
recommending precautions (such as the use of condoms) pending
characterization of the potential risk
· Discuss issues with the patient and let them know we do not know and let
them decide (5 members)
The Committees added a part "D" to require additional studies
- 9 members wanted more studies
Please
comment on whether further risk assessment should be done and whether any
cautionary language or recommendations should be made while additional risk
assessment is pending.
· Talk with the patients but don't scare them and let them decide
· We can only make recommendations on things we cannot enforce
6.)
What additional studies are needed?
Are these studies needed before or after approval of the product?
· There is a lot that is unknown and we need to know to make a decision
· Comprehension testing of the message before it is in full use
· Current data is inadequate for approval
· Need male reproductive studies before approval
· More discussion and movement on Risk Management Plan
· Study to demonstrate a better Risk - Benefit Ratio
· Require mandatory Adverse Event reporting
· More data on fracture and endocrine issues
· More animal (rabbit and mice) tests for low teratogenicity dose
General
Comments from the committee:
- Should have comparison of Accutane and
Trazodone for acne indication and publication of the results to show if it
works thus limiting the off label use of the drug since it has been
publicized as working at a professional meeting
- Concern that the drug is not being approved
due to potential off label use
- FDA needs to move forward on the Risk
Management Plan for Retinoids - do what ever it takes to solve outstanding
problems.
- Given the teratogenic risk of retinoids, one
key element of a risk benefit program is being sure that, that among
retinoids with likely to be equivalent teratogenic risk, the most
effective retinoid should used for a given indication. This makes the issue of off label use
particularly important for indications which include substantial numbers
of patients of child bearing potential.