Anacor Pharmaceuticals Announces Positive Results from the Second Phase 3 Trial of Tavaborole for Onychomycosis

  Anacor Pharmaceuticals Announces Positive Results from the Second Phase 3
  Trial of Tavaborole for Onychomycosis

    Anacor Will Host a Conference Call Today at 5pm ET to Discuss Results

Business Wire

PALO ALTO, Calif. -- February 28, 2013

Anacor Pharmaceuticals (NASDAQ:ANAC) today announced positive preliminary
results from the second of two Phase 3 trials of tavaborole (known as Study
302). Tavaborole is a topical anti-fungal for the treatment of onychomycosis,
a fungal infection of the nail and nail bed that affects approximately 35
million people in the United States. Results from the first Phase 3 trial
(known as Study 301) were announced on January 29, 2013. In both studies,
tavaborole achieved statistically significant and clinically meaningful
results on all primary and secondary endpoints.

“We are pleased with the results of this study and we are on track with our
plans to file an NDA in the middle of this year,” said David Perry, Chief
Executive Officer of Anacor. “In both Phase 3 trials, tavaborole demonstrated
better efficacy than ciclopirox lacquer, the only approved topical treatment
for onychomycosis. Importantly, ciclopirox lacquer requires concomitant nail
debridement. If approved, tavaborole could offer patients and prescribers a
safe, effective and convenient topical treatment option for onychomycosis.”

“In Study 302, tavaborole achieved a complete cure rate of 9.1% in a patient
population that we believe represents the majority of onychomycosis patients.
In both of our Phase 3 studies, we allowed enrollment of adult patients of all
ages who had up to 60% of their toenail affected by disease. While older
patients and those with more extensive disease may be tougher to treat, we
believe they represent an important and significant segment of the patient
population. Approximately fifty percent of people over the age of 70 have
onychomycosis, and often patients don’t seek treatment until the infection has
progressed and involves a significant portion of the nail,” said Lee Zane, MD,
Vice President of Clinical Development of Anacor. “In addition, 27.5% of
patients in Study 302 achieved a completely clear or almost clear nail, which
is a very meaningful endpoint to physicians and patients because it represents
an excellent clinical response.”

The results at week 52 for each of the Phase 3 studies are summarized in the
table below:

                                      Study 301           Study 302
                                      (reported 1/29/13)
                                      (active / vehicle)  (active / vehicle)
Primary Endpoint
“Complete cure” (a composite           6.5% / 0.5%
endpoint that requires both a         (p=0.001)           9.1% / 1.5%
completely clear nail and                                   (p<0.001)
mycological cure)                      
Secondary Endpoints
                                       26.1% / 9.3%
“Completely clear” or “almost clear”  (p<0.001)           27.5% / 14.6%
(≤10% clinical involvement) nail                            (p<0.001)
                                       
Mycological cure (the absence of       31.1% / 7.2%
fungus as determined by a negative     (p<0.001)            35.9% / 12.2%
potassium hydroxide (“KOH”)                               (p<0.001)
examination and a negative fungal      
culture)
                                       15.3% / 1.5%
“Completely clear” or “almost clear”  (p<0.001)           17.9% / 3.9%
nail with mycological cure                                  (p<0.001)
                                       
Other Results
                                       87.0% / 47.9%
Negative fungal culture               (p<0.001)           85.4% / 51.2%
                                                            (p<0.001)
                                       
                                       24.6% / 5.7%
“Completely clear” or “almost clear”  (p<0.001)           25.3% / 9.3%
nail and negative culture                                   (p<0.001)
                                       
                                                          

Tavaborole Phase 3 Study 302 Design

Study 302 enrolled 601 patients in the United States and Canada, randomized
two-to-one to receive either tavaborole, 5% solution or vehicle. Eligible
patients were at least 18 years of age (with no upper age limit) with a
clinical diagnosis of distal subungual onychomycosis involving 20% - 60% of
the total area of the target great toenail and positive mycology. Patients
were instructed to apply tavaborole solution or vehicle to the target great
toenail once daily for 48 weeks. Study 301 had an identical design but
enrolled patients in the United States and Mexico. Anacor received a Special
Protocol Assessment from theFDAon all major parameters of Studies 301 and
302, including study endpoints.

Safety

Overall, tavaborole was safe and well-tolerated across study subjects. There
were no serious adverse events related to study drug. The rate of
discontinuations as a result of adverse events was low (0.8% for tavaborole
and 0.5% for vehicle) in Study 302.

Conference Call and Webcast

Anacor will host a conference call today at 5:00 p.m. ET / 2:00 p.m. PT to
discuss these results. The call can be accessed by dialing (877) 291-1367
(domestic) and (914) 495-8534 (international) five minutes prior to the start
of the call. The call will also be webcast live and can be accessed on the
Events and Presentations page, under Investors, on the company’s website at
http://www.anacor.com and will be available for three months following the
call.

About Anacor Pharmaceuticals

Anacor is a biopharmaceutical company focused on discovering, developing and
commercializing novel small-molecule therapeutics derived from its boron
chemistry platform. Anacor has discovered eight compounds that are currently
in development. Its two lead product candidates are topically administered
dermatologic compounds — tavaborole, a topical antifungal for the treatment of
onychomycosis, and AN2728, a topical anti-inflammatory PDE-4 inhibitor for the
treatment of atopic dermatitis and psoriasis. In addition to its two lead
programs, Anacor has discovered three other wholly-owned clinical product
candidates — AN2718 and AN2898, which are backup compounds to tavaborole and
AN2728, respectively, and AN3365 (formerly known as GSK2251052, or GSK‘052),
a systemic antibiotic for the treatment of infections caused by Gram-negative
bacteria, which previously was licensed to GlaxoSmithKlineLLC, or GSK. GSK
has returned all rights to the compound to us and we are considering our
options for further development, if any, of this compound. We have discovered
three other compounds that we have out-licensed for further development — two
compounds for the treatment of animal health indications that are licensed to
Eli Lilly and Company and AN5568, also referred to as SCYX-7158, for human
African trypanosomiasis (HAT, or sleeping sickness), which is licensed to
Drugs for Neglected Diseases initiative, or DNDi. We also have a pipeline of
other internally discovered topical and systemic boron-based compounds in
development. For more information, visit http://www.anacor.com.

Forward-Looking Statements

This press release may contain forward-looking statements that relate to
future events including the development of tavaborole, timing for filing of a
new drug application, or NDA, related to tavaborole and the potential for
approval and commercialization of tavaborole. These forward looking statements
involve known and unknown risks, uncertainties and other factors that could
cause actual levels of activity, performance or achievement to differ
materially from those expressed or implied by these forward-looking
statements, including risks related to the planned NDA filing, risks from
competition for tavaborole (in particular efinaconazole from Valeant
Pharmaceuticals International Inc.), whether the information of the key
opinion leaders is representative of the behavior and opinions of other
investigators, risk of unforeseen side effects and risks related to regulatory
approval and commercialization of new drug candidates. These and other risks
are described in more detail in Anacor’s Annual Report on Form 10-K for the
year ended December 31, 2011, filed with the Securities and Exchange
Commission under the heading “Risk Factors” and Anacor’s subsequent Quarterly
Reports on Form 10-Q. These statements reflect the views of Anacor as of the
date of this press release with respect to future events and, except as
required by law, it undertakes no obligation to update or revise publicly any
forward-looking statements, whether as a result of new information, future
events or otherwise after the date of this press release.

Contact:

Anacor Pharmaceuticals
DeDe Sheel, 650-543-7575
Director, Investor Relations and Corporate Communications