Bull. Org. mond. Sante 1967, 36, 303-308 Bull. Wld Hlth Org. The Haemolytic Effect of Various Regimens of Primaquine with Chloroquine in American Negroes with G6PD Deficiency and the Lack of an Effect of Various Antimalarial Suppressive Agents on Erythrocyte Metabolism* G. J. BREWER 1 & C. J. D. ZARAFONETIS 2 In view of the fact that increased resistance to drugs by malaria parasites in some parts ofthe world may lead to increasing use ofa combination ofprimaquine with chloro- quine for chemotherapy, studies were made on the severity of the haemolytic anaemia induced by 45 mg primaquine in American Negroes with glucose-6-phosphate dehydro- genase deficiency. It was found that twice-weekly administration ofprimaquine induced more haemolysis than once-weekly administration, and that administration once weekly for 4 weeks and twice weekly thereafter resulted in a degree of anaemia falling between those produced by the other regimens. Anaemia was not-induced in controls with no G6PD deficiency. One volunteer developed an intercurrent infection that was treated with salicylates; his haemolysis was markedly intensified, but whether by the infection, the salicylates or both could not be determined. In a conjoint study, the administration of six malaria-suppressive drugs had no detectable effect on the activities of several erythrocyte enzymes or on the levels of adenosine monophosphate, diphosphate or triphosphate. I. THE HAEMOLYTIC EFFECT OF VARIOUS REGIMENS OF PRIMAQUINE WITH CHLOROQUINE IN AMERICAN NEGROES WITH G6PD DEFICIENCY This study was conducted to obtain information primaquine combined with chloroquine.3 Con- on the severity of the haemolytic anaemia induced in siderable information has accumulated on dosage Negro male subjects deficient in glucose-6-phosphate response in terms of haemolytic anaemia after daily dehydrogenase (G6PD) by various regimens of primaquine administration (Kellermeyer et al., 1961) but little information is available concerning * The work reported in this paper was supported in major the haemolytic effects from once-weekly (Cahn & part by the Research and Development Command, Office Levy, 1962; Alving et al., 1960) or twice-weekly of the Surgeon General, Department of the Army, under contract DA-49-193-MD-2876 with the Department of primaquine administration. One of the presently Medicine, University of Michigan, and in part by USPHS recommended antimalaria regimens (Alving et al., Grant AM09381 and USPHS Career Development Award 1-K3-AM 7959 (Dr Brewer). Contribution No. 150 from the 1960) calls for administration of once-weekly doses Army Research Program on Malaria. of 45 mg of primaquine 4 combined with 300 mg 1 Assistant Professor, Department of Medicine (Simpson Memorial Institute), and Research Associate, Department of Human Genetics, University of Michigan Medical School, 3Haemolysis from primaquine+chloroquine combi- Ann Arbor, Mich., USA. nations in Negroes deficient in G6PD is thought to result ' Professor, Department of Medicine, and Director, solely from the primaquine. Simpson Memorial Institute, University of Michigan ' All dosages in this paper are given in terms of mg Medical School, Ann Arbor, Mich., USA. of base. 1951 303 304 G. J. BREWER & C. J. D. ZARAFONETIS chloroquine. It is possible that increased resistance drug administration. All G6PD-deficient volunteers of malaria parasites in some areas of the world may were of the Negro race. Controls were from[both result in an increased frequency of administration of the Negro and the Caucasian races. this drug combination (Young & Moore, 1961; Powell et al., 1963, 1964a, 1964b). It is important to have information on the degree of increased haemo- RESULTS lysis in G6PD-deficient individuals resulting from Drug administration to non-deficient subjects did the increased dose of drug. Accordingly, comparative not result in haemolysis. The results of the studies evaluation of the haemolytic effects of various drug of the haemolytic effect of the three regimens of regimens has been carried out. primaquine+ chloroquine in G6PD-deficient subjects are summarized in Table 1. In this table, the baseline METHODS, SUBJECTS, AND EXPERIMENTAL DESIGN averages for haemoglobin and haematocrit values are given, followed by the nadir values. The nadir Deficiency of G6PD was detected by use of the has been arbitrarily designated as the lowest value methaemoglobin reduction test (Brewer et al., 1960). and and the value preceding and the value following the Haematocrit and haemoglobin determinations, lowest value. This is followed in the table by the reticulocyte counts, were performed by standard methods. The for these average of the three nadir values. The figures in haematological subjects the next column, the decrease in haemoglobin and studies were all volunteer inmates of the Southern haematocrit values, were determined by subtracting Michigan Prison, Jackson, Mich., USA. Approxim- nadir 500 inmates were screened for G6PD the average from the baseline average. The ately Negro day of the nadir is also shown, counting day zero as deficiency in order to detect deficient subjects for the primaquine+chloroquine study. The available en- the first day of drug administration. In Group II1, one deficient subject (Case No. 39) had an unusually zyme-deficient subjects, along with an equal number an inter- were divided into three severe reaction, apparently provoked by of non-deficient controls, current which was sali- groups of 8 subjects each, and were given drug febrile illness, treated by according to the following plan: cylates. Group I (administration of drug once weekly). Group I: administration of 45 mg primaquine Most subjects had a relatively minimal, asympto- and 300 mg chloroquine once weekly. matic haemolytic episode. One subject, No. 4, com- Group II: administration of 45 mg primaquine plained of an upset stomach, nervousness and loss and 300 mg chloroquine twice weekly. of sleep early during haemolysis. Haematological Group III: administration of 45 mg primaquine recovery was complete in 8 weeks in all volunteers. and 300 mg chloroquine once weekly for 4 weeks, Group II (administration of drug twice weekly). then twice weekly. In general, the haemolytic episodes were slightly The subjects were given their medication on Mon- more acute in onset and slightly more marked than day mornings for once-a-week programmes, and in Group I. Symptoms, however, were minimal. on Monday and Thursday mornings for twice-a- One subject, No. 19, developed symptoms of an week programmes. The medication was a combined upper respiratory infection with no apparent 45-mg primaquine and 300-mg chloroquine tablet as exacerbation of haemolysis. Haematological reco- supplied by the US Army Medical Research and very was complete in 8 weeks, except in one case Development Command. Blood samples (5 ml in in whom recovery took 10 weeks. ethylene-diamine-tetracetic acid) were taken thrice Group III (administration of drug once weekly weekly for haematocrit and haemoglobin determina- for 4 weeks followed by twice weekly). The purpose tions. Normal individuals were maintained on their of this group was to find out whether the somewhat programme for a total of 8 weeks. G6PD-deficient more acute haemolytic anaemia associated with the individuals were maintained on their programmes twice-weekly drug dose of Group II could be avoided a sufficient period of time to permit return of their by the preliminary administration of once-weekly haemoglobin and haematocrit levels to pre-drug, doses for 4 weeks in order gradually to destroy a baseline values; this occurred by 8 weeks in most portion of the susceptible red cells (the older red men and by 10 weeks in all volunteers. Three baseline cells). In general, this objective was achieved. The values were obtained for each volunteer prior to volunteers tolerated the subsequent regimen of HAEMOLYTIC EFFECT OF PRIMAQUINE/CHLOROQUINE IN G6PD-DEFICIENT SUBJECTS 305 TABLE I RESULTS IN NEGRO MALES WITH G6PD DEFICIENCY RECEIVING 45 mg PRIMAQUINE AND 300 mg CHLOROQUINE IN DIFFERENT REGIMENS Decrease ParameterParamete Average Nadir after drug Average verage(bslnavrgbsln CaseCsNoNo. measured ofA3 Vbaseline (lowestoinpoint and valuesvas IA esS minus9Caaverage Day of nadirwk vbaselInestvalues on eandeeach side) values ~~of 3 lowest v~alues) Group I: Administration once weekly 4 Hb 14.4 11.8 11.8 12.3 11.9 2.5 9 Hct 45 39 37 40 39 6 11 6 Hb 13.1 12.8 12.3 12.6 12.6 0.5 7 Hct 41 41 40 41 41 0 9 8 Hb 16.0 14.1 13.8 14.4 14.1 1.9 7 Hct 46 43 42 44 43 3 16 10 Hb 14.7 13.8 12.8 13.3 13.3 1.4 7 Hct 46 42 40 41 41 5 9 11 Hb 14.3 12.6 11.1 12.6 12.1 2.2 11 Hct 45 40 38 42 40 5 11 12 Hb 15.2 14.3 13.3 13.3 13.6 1.6 32 Hct 45 43 42 43 43 2 18 13 Hb 14.1 12.2 12.0 12.6 12.3 1.8 11 Hct 46 40 37 38 38 8 7 16 Hb 15.0 15.4 13.3 14.3 14.3 0.7 9 Hct 48 47 44 46 44 4 16 Group II: Administration twice weekly 17 Hb 14.5 12.8 12.6 12.8 12.7 1.8 11 Hct 45 40 39 39 39 6 7 18 Hb 16.3 13.1 12.3 13.1 12.8 3.5 11 Hct 50 43 42 42 42 8 9 19 Hb 14.7 12.3 10.8 11.5 11.5 3.2 14 Hct 45 40 35 35 37 8 14 26 Hb 14.9 12.5 12.2 13.1 12.6 2.3 9 Hct 45 39 38 39 39 6 7 29 Hb 15.3 14.9 13.6 15.1 14.5 0.8 7 Hct 50 45 45 49 46 4 18 30 Hb 15.1 11.6 11.3 11.8 11.6 3.5 11 Hct 47 37 36 36 36 11 9 31 Hb 14.7 12.8 11.2 11.3 11.8 2.9 9 Hct 44 40 39 42 40 4 it 32 Hb 13.6 13.1 11.5 12.0 12.2 1.4 14 Hct 43 37 35 36 36 7 9 Group Ill: Administration once weekly for 4 weeks, then twice weekly 35 Hb 15.9 14.6 12.8 13.8 13.7 2.2 9 Hct 49 45 41 43 43 6 9 36 Hb 13.6 12.9 12.6 13.1 12.9 0.7 11 Hct 44 41 39 41 40 4 9 37 Hb 14.7 14.6 12.5 13.1 13.4 1.3 4 Hct 43 39 38 40 39 4 7 38 Hb 15.8 14.9 11.8 12.6 13.1 2.7 9 Hct 47 44 34 40 39 8 9 39 Hb 13.2 10.8 9.2 9.5 9.8 3.4 32 Hct 43 30 29 30 30 13 35 44 Hb 13.6 11.5 11.0 12.0 11.5 2.1 14 Hct 45 39 37 40 39 6 42 45 Hb 15.7 14.6 13.3 15.1 14.3 1.4 37 Hct 46 45 39 45 43 3 9 46 Hb 12.5 10.5 10.2 11.0 10.6 1.9 14 Hct 39 37 34 36 36 3 9 a3 Haemoglobin (Hb) in g/100 ml and haematocrit (Hct) in vol.