Split on AMD Drugs
bevacizumab favored in 2006 PAT survey results.
E. MATHIS, PhD, MEDICAL EDITOR
of the American Society of Retina Specialists (ASRS) 2006 Practices and Trends (PAT)
survey of its members indicate that there is not yet a consensus as to the most
effective treatment for wet age-related macular degeneration (AMD), though off-label
bevacizumab (Avastin, Genentech) and recently approved ranibizumab (Lucentis, Genentech)
are the clear leaders over other therapies.
The lack of a head-to-head study comparing the relative safety
and efficacy of ranibizumab and bevacizumab surely accounts for the lack of
consensus. However, the recent announcement by the National Institutes of Health
that it will fund a large-scale, 2-year, head-to-head study of the two Genentech
drugs was welcomed by the retina community.
Though the PAT survey was conducted prior to the June 30 FDA approval
of ranibizumab, survey results show that, were the drug available at the time of
the survey, it would rival bevacizumab and far outrank other interventions in the
treatment of AMD.
For instance, in the case of AMD with classic-type lesions, the
respondents polled, given a multiple choice of treatments, chose equally (34% each)
bevacizumab and ranibizumab. Photodynamic therapy (PDT) with a vascular endothelial
growth factor (VEGF) blocking drug (13.5%) and PDT with steroids (11%) followed
third and fourth, respectively.
When the same question was asked with the only difference being
occult-type membranes rather than classic-type lesions, respondents overwhelmingly
(84%) chose bevacizumab and ranibizumab, but again in the same percentage (42% each).
Other therapies only received single percentages.
With the FDA's approval of ranibizumab, it is clear that it will
be frequently used by retinal physicians for the treatment of AMD, both with classic-type
and occult-type lesions. This is even more clear when it is considered that 95%
respondents to last year's PAT Survey were treating AMD with either PDT alone or
PDT with steroid.
An interesting finding in this year's PAT Survey is how respondents
answered the question of how they would want themselves treated for juxtafoveal
lesions. In these cases, physicians were far more conservative. While ranibizumab
(36%) and bevacizumab (16%) still accounted for a slim majority of the responses,
PDT with an anti-VEGF (28.5%) outranked bevacizumab alone, and 11% chose old-style
standard laser therapy.
HOW THE PAT SURVEY IS CONDUCTED
This year's results were reported in September
at the 24th Annual ASRS Meeting and the 6th Annual European VitreoRetinal Society
(EVRS) Meeting in Cannes, France.
The PAT Survey, as its title suggests, measures the professional
habits, treatment regimens, and other information about retinal specialists. After
a short section to gather basic demographic information (location, practice information,
etc.), the survey moves into questions about how the responding physician treats
conditions such as AMD, retinal vascular occlusion (RVO), and diabetic retinopathy.
The survey also asks which procedures retinal physicians are using to treat these
disorders and reports in what numbers these interventions are being used. Necessarily
the questions of the survey are dictated to some extent by developments in the field
of retinal disease.
The testing environment itself has also changed over the past
7 years, with Internet administration of the survey replacing more structured administrations
previously done exclusively on paper. This has allowed the respondents the ability
to answer more at their leisure. As the rate of response for the PAT Survey had
already grown significantly between 1999 and 2004, one can only assume that Internet
administration of the survey had increased the response numbers even more.
The PAT survey "has taken on a life of its own since it began
in 1999," said Robert A. Mittra, MD, editor of the survey for ASRS, during a conversation
with Retinal Physician. The survey has been "fueled by the retinal community's
interest of the latest preferences and trends among their peers," Dr. Mittra said.
Noting the survey's impact on the retinal community, Dr. Mittra stated, "It is quoted
frequently in scientific lectures and publications and is used to help support legislative
efforts such as the successful American Academy of Ophthalmology (AAO) effort to
convince Centers for Medicare & Medicaid Services (CMS) to reimburse Avastin."
STEROIDS FOR RVO GAIN GROUND
Other interesting responses to the survey
were on the subject of central RVO. For the management of4-month-old RVO with
cystoid macular edema (CME), half (50%) of the respondents chose intravitreal steroid
as the treatment they would use. Coming in second was treatment with bevacizumab
at 38%. Ranibizumab was not offered as a choice here, though "Other" was a
choice offered to respondents, and ranibizumab users could have answered thus.
When asked how they would treat 4-month-old branch RVO with CME,
the number of respondents who chose bevacizumab dropped to 14%, behind standard
grid laser (38%), laser therapy plus intravitreal steroid (29%), and intravitreal
steroid alone (16%). These responses on RVO would seem to indicate that a trend
toward use of anti-angiogenic drugs similar to that in treatment of AMD has not
REMAINS TO BE SEEN
Of course, these results are merely the
tip of the iceberg, and Dr. Mittra reminds Retinal Physician that "there
were many more interesting results revealed in the survey that can be viewed on
the ASRS Web site (see editor's note)." Dr. Mittra concluded, "The continued success
and value of this survey depends on all in the retinal community taking a few minutes
to respond to the survey each year."
Editor's note: The results of the ASRS 2006 PAT Survey are available
to ASRS members at
Retinal Physician, Issue: November 2006