Table 2.
Chemoprophylactic efficacy of TQ
| Serial no | Study design | Study site | Study participant | Outcome measure | Intervention arms | Efficacy/relapse rate (95% CI), n | References |
|---|---|---|---|---|---|---|---|
| 1 | Randomized, placebo-controlled, double-blinda human challenge model | Experimental study: USA | Six normal volunteers | Rate of positive blood smears in 65 d (P. falciparum) | TQ 600 mg single dose Placebo |
25% (0–67.4), 4 100%, 2 |
89 |
| 2 | Randomized, double-blind, placebo-controlled chemoprophylaxis trial | Ghana | 509 health volunteers | Protective efficacy relative to placebo in 16 wks (4 wks after the last dose; P. falciparum) | TQ 200 mg/d for 3 d + weekly TQ 100 mg/d for 3 d + weekly TQ 50 mg/d for 3 d + weekly TQ 25 mg/d for 3 d + weekly MQ 250 mg weekly Placebo |
85.6% (76.2–91.6), 91 87.2% (78.3–92.7), 94 84.4% (74.8–90.7), 91 31.8% (20.2–43.4), 93 85.7% (71.9–93.3), 46 |
90 |
| 3 | Double-blind, placebo-controlled, randomized study | Kenya | 225 health volunteers | Protective efficacy relative to placebo in 13 wks (1 wk after the last dose; P. falciparum) | TQ 400 mg/d for 3 d + weekly TQ 400 mg/d for 3 d TQ 200 mg for 3 d + weekly Placebo |
89% (77–95), 57 68% (53–79), 54 86% (73–93), 53 |
91 |
| 4 | Randomized, double-blind, placebo-controlled study | Thailand | 205 participants | Rate of positive blood smears during 6 months (P. vivax and P. falciparum) | TQ 400 mg/d for 3 d +400 mg monthly Placebo |
1% (0–3.0), 96b 32.6% (23–42.2), 92c |
98 |
| 5 | Randomized, placebo-controlled study | Gabon | 410 Gabonians | Rate of positive blood smears by day 77 (P. falciparum) | TQ 250 mg/d for 3 d TQ 125 mg/d for 3 d TQ 62.5 mg/d for 3 d TQ 31.3 mg/d for 3 d Placebo |
0%, 84 1.3% (0–3.8), 79 3.5% (0–7.4), 86 20.3% (11.4–29.2), 79 17.1% (8.9–25.2), 82 |
92 |
| 6 | Randomized, double-blind, controlled Phase III study | East Timor | 654 Australian soldiers | Rate of positive vivax blood smears in 6 months | TQ 200 mg/d for 3 d + weekly MQ 250 mg/d for 3 d + weekly |
0.9% (0.07–1.7), 492 0.7% (0–1.98), 162 |
93 |
Notes:
a
TQ concentration in the oligosymptomatic case was one half of that in the protected individuals.
b
One vivax case.
c
30 cases, 21 vivax and eight falciparum cases and one mixed infection.
Abbreviations: TQ, tafenoquine; 95% CI, 95% confidence interval; P. falciparum, Plasmodium falciparum; wk, week; d, day; MQ, mefloquine; P. vivax, Plasmodium vivax.