feature
Travoprost
Develops a Strong Track Record for Safety and Efficacy
New studies show travoprost lowers IOP and
sustains lasting effects. These findings and others that show travoprost's efficacy
and safety may encourage clinicians to use the drug in more patients to promote
better outcomes.
By Judith Springer Riddle, Senior Editor
New
data on the safety and efficacy of travoprost 0.004% (TRAVATAN®
solution) show this agent sustained lower IOPs than latanoprost 0.005% (XALATAN*)
in glaucoma patients throughout a 24-hour period and beyond.
Other research found that travoprost had lasting
effects on diurnal and nocturnal IOP even after it was discontinued for 41 to
63 hours.
One particular carbonic anhydrase inhibitor,
when added to travoprost therapy, showed excellent additivity in lowering
IOP.
In a large clinical study (n=690),
a travoprost BAK-free formulation was shown to have equivalent IOP-lowering efficacy
to the currently marketed travoprost 0.004%.
Here are the specifics of these latest
study findings that could lead to better visual outcomes in glaucoma patients:
Lasting effects of travoprost on diurnal and nocturnal intraocular
pressure
Recent studies suggest the IOP-lowering effects
of prostaglandin analogues can persist well beyond the standard 24-hour dosing schedule.
To confirm these findings, Sit, Weinreb
and colleagues investigated the diurnal and nocturnal persistence of IOP reduction
after discontinuing one or two doses of travoprost in patients with open-angle glaucoma
(OAG) or ocular hypertension (OHT). In this prospective, open-label study, 20 patients
underwent three 24-hour sessions of IOP monitoring. The first (baseline) session
occurred before therapy was initiated in newly diagnosed patients or after a 4-week
washout period for those switching to travoprost. Patients administered travoprost
0.004% to both eyes once daily at bedtime.
A second monitoring session occurred
after 4 weeks or more of travoprost treatment. One to 8 weeks later, a third session
was performed 41 to 63 hours after the last travoprost dose.
At all times throughout the second
and third 24-hour monitoring periods, IOPs on treatment and off treatment were lower
than the corresponding baseline IOPs.
IOP reduction was sustained 41
to 63 hours after eliminating one to two doses of travoprost.
Researchers believe these findings
may result from persistent structural and biochemical remodeling in the uveoscleral
outflow pathway.
Sit AJ, Weinreb RN, Crowston JG, et
al. Sustained effect of travoprost on diurnal and nocturnal intraocular pressure.
Am. J Ophthalmol. 2006;141:1131-1133.
Travoprost sustains lower IOP readings than latanoprost over
a 24-hour period
In this study, researchers compared travoprost
0.004% to latanoprost 0.005% to determine which prostaglandin analogue was better
at sustaining lower IOP readings over a 24-hour period in patients with OAG
or OHT.
During
the patient eligibility visit, investigators measured IOPs every 4 hours throughout
a 24-hour period. They randomized 62 patients to receive either one drop of travoprost
(n=32) or latanoprost (n=30) each evening for 2 weeks. At week 2, investigators
measured IOPs every 4 hours throughout two consecutive 24-hour periods.
The results: Travoprost produced
lower mean IOPs than latanoprost at all time periods, and IOPs were significantly
lower for the travoprost group at 12, 16, 20, 24, 36, 40 and 48 hours after the
last dose.
Feijoo JG, Martinez-de-la-Casa JM,
et al. A Comparison of the IOP Lowering Efficacy of Travoprost 0.004% and Latanoprost
0.005% Over a 24 Hour Period. Presented at The Association for Research in Vision
and Ophthalmology; April 30-May 4, 2006; Fort Lauderdale, FL.
Travoprost and latanoprost: efficacy vs. safety
Travoprost 0.004% was compared with latanoprost
0.005% in this prospective comparison study to measure safety and efficacy in lowering
IOPs over a 24-hour period in exfoliative glaucoma patients.
In this trial, 40 patients with IOPs
of 24 mm Hg or higher were randomized to receive either latanoprost or travoprost
for an 8-week treatment period. Subjects were then switched to the opposite
treatment for another 8 weeks. At baseline and at the end of each treatment
session, researchers assessed IOP readings for 24 hours at 6 a.m., 10 a.m.,
2 p.m., 6 p.m., 10 p.m. and 2 a.m.
Researchers found that travoprost produced
significantly lower IOPs throughout the 24 hours and a statistically lower pressure
at 6 p.m.
Konstas A, Vassilios KP, Ioannis KE,
et al. 24-hour IOP Efficacy and Safety of Latanoprost 0.005% versus Travoprost 0.004%
Each Given Every Evening in Exfoliative Glaucoma Patients. Presented at the World
Ophthalmology Congress; February 19-24, 2006; Saõ Paulo, Brazil (submitted
for publication).
A comparison of brinzolamide 1% vs. brimonidine 0.15% when
added to travoprost in glaucoma patients
Although it's common practice to add carbonic
anhydrase inhibitors and alpha2 agonists to prostaglandin analogues to lower IOPs
in glaucoma patients, few studies have been done to confirm their additive effects.
Feldman and colleagues conducted the
first prospective, double-masked study to compare the efficacy of brinzolamide
1% (AZOPT® suspension) and brimonidine 0.15% (ALPHAGAN* P) when
added to travoprost 0.004% in glaucoma patients.
Researchers studied the effects of
each drug when added to travoprost in 163 patients, age 35 years and older, at 17
centers. Seventy-nine patients were given brimonidine 0.15%, while 84 received brinzolamide
1% twice a day for 3 months in addition to travoprost.
Results showed patients receiving brinzolamide
1% achieved a mean diurnal IOP decrease of 2.9 mm Hg at 3 months versus 2.1
mm Hg in patients receiving brimonidine 0.15% (p=0.035).
Researchers concluded that adding brinzolamide
to travoprost lowers IOP more so than adding brimonidine at 8 a.m., 4 p.m.
and diurnal.
Feldman
RM, Prager TC, et al. Additivity of Brinzolamide vs. Brimonidine 0.15% to Travoprost
0.004%. Presented at The Association for Research in Vision and Ophthalmology; April
30-May 4, 2006; Fort Lauderdale, FL.
Comparison of travoprost with and without BAK for
safety and efficacy
Benzalkonium chloride (BAK) has long been known
for lowering the risk of bacterial contamination in glaucoma medications, thus increasing
their shelf life. But its propensity to cause ocular damage in patients continues
to spur introductions of new preservative-free drug formulations.
In a recent double-masked, randomized
multicenter trial, investigators compared the safety and efficacy of the newly formulated
travoprost 0.004% made without BAK to the currently marketed travoprost 0.004% containing
the preservative in patients with open-angle glaucoma or ocular hypertension.
Adult patients with OAG or OHT with
IOPs of 24 mm Hg to 36 mm Hg at 8 a.m., and 21 mm Hg to 36 mm Hg at 10 a.m. and
4 p.m., in at least one eye, received either travoprost 0.004% preserved with BAK
(n=346) or travoprost BAK-free (n=344) once daily in the evening.
Researchers measured IOPs at 8 a.m.,
10 a.m. and 4 p.m. at week 2, week 6 and month 3 of the study. Mean IOP reductions
across nine study visits ranged from 7.3 mm Hg to 8.5 mm Hg for travoprost BAK-free
and from 7.4 mm Hg to 8.4 mm Hg for travoprost 0.004%.
The number of adverse events and the
patients who discontinued therapy because of them were similar for both treatment
groups. The study reported 6.4% of subjects treated with travoprost BAK-free experienced
hyperemia. Researchers concluded travoprost BAK-free was equivalent to travoprost
0.004% in both safety and efficacy.
Lewis RA, Weiss MJ, Landry TA, et al.
Travoprost 0.004% With and Without Benzalkonium Chloride: A Comparison of Safety
and Efficacy. Presented at The Association for Research in Vision and Ophthalmology;
April 30-May 4, 2006; Fort Lauderdale, FL.
Travoprost lowers IOP better than latanoprost in a 6-week
comparison, open label study
At the 2006 annual meeting of the American Glaucoma
Society, Maul and colleagues presented the results of a randomized, double-masked
study that compared the IOP-lowering efficacy and safety of travoprost 0.004% with
latanoprost 0.005% when dosed once daily for 6 weeks in patients with OAG or OHT.
For 6 weeks in this study, 155 patients
received travoprost 0.004% while 147 patients received latanoprost 0.005%.
The medications were administered once
daily at 9 p.m. Researchers measured IOPs at 5 p.m. This 6-week study included
visits at screening, eligibility and during weeks 1, 2, 4 and 6.
Mean IOP values were lower for travoprost
at all time points during the study. Differences in mean IOP change from baseline
for the four on-therapy visits all favored travoprost. The difference in pooled
IOP reductions from baseline was statistically significant: 8.3 mm Hg for travoprost
and 7.5 mm Hg for latanoprost during the masked phase of the study.
Researchers found that travoprost 0.004%
produced significantly greater IOP-lowering effects compared to latanoprost
0.005% at 5 p.m., approximately 20 hours after dosing.
Maul E, Carrasco FG, Costa VP, et al.
A Six-Week Double-Masked Study Comparing Travoprost 0.004% to Latanoprost 0.005%
Followed by a Six-Week Open-Label Treatment on Travoprost 0.004%. Presented at the
American Glaucoma Society annual meeting, March 2-5, 2006, Charleston, SC.
Optometric Management, Issue: August 2006