New developments in anti-malarial target candidate and product profiles

Malaria Journal

Table 5 Profiles for TCP-3, activity against hypnozoites (mainly Plasmodium vivax)

TCP3: general considerations	Minimum essential	Ideal
Dosing regimen; adult/pediatric dose	Oral, single dose (predicted) <1000 mg/<250 mg; oral, three doses <400 mg/<100 mg for areas of multidrug resistance	Oral, single dose (predicted); <100 mg/25 mg
Efficacy	In combination, prevents 80% of relapses^a over 6 months	In combination, prevents 80% of relapses over a year^a
Safety and tolerability	Therapeutic ratio >tenfold between therapeutic exposure and NOAEL in preclinical studies and easily monitorable adverse event or biomarker for human studies	Therapeutic ratio >50-fold between therapeutic exposure and NOAEL in preclinical studies and easily monitorable adverse event or biomarker for human studies
G6PD deficiency status^b	Therapeutic dose shows minimal differential change in hemoglobin concentration in mild and moderate G6PD deficient patients compared to patients with normal activity levels. New candidate drug shows no enhanced hemolytic risk in preclinical model	Therapeutic dose shows no significant change in hemoglobin concentration
Formulation	Acceptable clinical formulation identified which can be co-formulated with currently used blood schizonticides	Acceptable clinical formulation identified which can be co-formulated with currently used blood schizonticides

^aCurrently it is not possible to separate relapse from recrudescence of P. vivax. The ideal efficacy of 90% is based on the values seen for both primaquine and tafenoquine in its phase II study
^bThe current benchmark would imply a lower degree of hemolysis in severely G6PD-deficient patients, with no additional safety signal requiring monitoring in the field

ISSN: 1475-2875