A multicenter, randomized, double-blind, placebo-controlled, 8-week trial of the efficacy and tolerability of once-daily losartan 100 mg/hydrochlorothiazide 25 mg and losartan 50 mg/hydrochlorothiazide 12.5 mg in the treatment of moderate-to-severe essential hypertension.
BACKGROUND
Many patients with moderate-to-severe hypertension require multiple drug therapy to achieve blood-pressure goals. Fixed-dose combination therapy with losartan and hydrochlorothiazide may be useful in this population.


OBJECTIVE
This study was conducted to obtain additional data on the antihypertensive efficacy and tolerability of once-daily, fixed-dose combinations of losartan and hydrochlorothiazide.


METHODS
This was a multicenter, randomized, double-blind, parallel-group, placebo-controlled trial. Patients > or = 21 years of age with moderate-to-severe essential hypertension, defined as a mean trough sitting diastolic blood pressure (SiDBP) of 105 to 115 mm Hg, were randomly assigned in a 2:2:1 ratio to receive losartan 100 mg/hydrochlorothiazide 25 mg (L100/25), losartan 50 mg/hydrochlorothiazide 12.5 mg (L50/12.5), or placebo (PBO) once daily for 8 weeks. The primary efficacy measurement was the mean change from baseline in trough SiDBP in the L100/25 versus L50/12.5 treatment groups. Responders were defined as patients with mean trough SiDBP <90 mm Hg or a > or = 10-mm Hg decrease in mean trough SiDBP.


RESULTS
A total of 446 patients were randomly assigned to receive L100/25 (n = 173), L50/12.5 (n = 184), or PBO (n = 89). At week 8, mean trough SiDBP was significantly lower than at baseline in the L100/25 (-17.5 mm Hg), L50/12.5 (-15.2 mm Hg), and PBO groups (-8.5 mm Hg) (all P < 0.001). The difference between the active-treatment groups was statistically significant (-2.2 mm Hg; 95% Cl, range -3.8 to -0.6) (P = 0.006), as was the difference between the L100/25 and PBO groups (-9.0 mm Hg; 95% CI, range -I1.0 to -7.0) (P < 0.001) and the L50/12.5 and PBO groups (-6.7 mm Hg; 95% CI, range -8.7 to -4.8) (P < 0.001). At week 8, the percentages of responders were 86.7% (144 of 166), 78.9% (142 of 180), and 50.0% (42 of 84) in the L100/25, L50/12.5, and PBO groups, respectively. The incidence of adverse experiences (AEs) was 34.7% (60 of 173) in the L100/25 group, 23.9% (44 of 184) in the L50/12.5 group, and 32.6% (29 of 89) in the PBO group. The incidence of drug-related AEs was similar among the treatment groups (L100/25, 7.5% [13 of 173]; L50/12.5, 7.1% [13 of 184]; and PBO, 11.2% [10 of 89]).


CONCLUSIONS
This study demonstrates the antihypertensive efficacy and tolerability of the once-daily, fixed-dose combination L50/12.5 in patients with moderate-to-severe essential hypertension. In this study, L100/25 provided additional anti-hypertensive efficacy beyond that of L50/12.5 (and both were more efficacious than PBO). Approximately 4 of 5 patients (78.9%) treated with L50/12.5 responded to therapy, as did nearly 9 of 10 patients (86.7%) treated with L100/25. The tolerability profiles of L50/12.5 and L100/25 were similar to that of PBO.
Western Pennsylvania Hospital, Pittsburgh, USA.
Alan H
AH
Gradman
William E
WE
Brady
Lisa P
LP
Gazdick
Paulette
P
Lyle
Robert K
RK
Zeldin
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D057911:Angiotensin Receptor Antagonists; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004338:Drug Combinations; D005260:Female; D006801:Humans; D006852:Hydrochlorothiazide / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy*; D019808:Losartan / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011674:Pulse; D012720:Severity of Illness Index; D016896:Treatment Outcome
D057911:Angiotensin Receptor Antagonists; D000959:Antihypertensive Agents; D004338:Drug Combinations; D006852:Hydrochlorothiazide; D019808:Losartan