A randomized, parallel study of the safety and efficacy of 45 mg primaquine versus 75 mg bulaquine as gametocytocidal agents in adults with blood schizonticide-responsive uncomplicated falciparum malaria [ISCRTN50134587].

BACKGROUND: The WHO recommends that adults with uncomplicated P. falciparum successfully treated with a blood schizonticide receive a single dose of primaquine (PQ) 45 mg as a gametocytocidal agent. An earlier pilot study suggested that 75 mg of bulaquine (BQ), of which PQ is a major metabolite, may be a useful alternate to PQ. METHODS: In a randomized, partial blind study, 90 hospitalized adults with Plasmodium falciparum malaria that was blood schizonticide-responsive and a gametocytemia of > 55/microl within 3 days of diagnosis were randomized to receive single doses of either PQ 45 mg or BQ 75 mg on day 4. We assessed gametocytemia on days 8, 15, 22 and 29 and gametocyte viability as determined by exflagellation (2 degrees end point) on day 8. RESULTS: On day 8, 20/31 (65%) primaquine recipients versus 19/59 (32%) bulaquine recipients showed persistence of gametocytes (P = 0.002). At day 15 and beyond, all patients were gametocyte free. On day 8, 16/31 PQ and 7/59 BQ volunteers showed gametocyte viability (p = 0.000065). CONCLUSION: BQ is a safe, useful alternate to PQ as a Plasmodium falciparum gametocytocidal agent and may clear gametocytemia faster than PQ.

A randomized, double-blind, parallel-group, comparative safety, and efficacy trial of oral co-artemether versus oral chloroquine in the treatment of acute uncomplicated Plasmodium falciparum malaria in adults in India.

In India, treatment of acute, uncomplicated Plasmodium falciparum malaria is becoming increasingly difficult due to resistance to chloroquine, thus there is a need for new antimalarial drugs. CGP 56697 (co-artemether), a new drug, is a combination of artemether and lumefantrine in a single oral formulation (one tablet = 20 mg of artemether plus 120 mg of lumefantrine). In a double-blind study, 179 patients with acute uncomplicated P. falciparum malaria were randomly assigned to receive either CGP (n = 89) given as a short course of 4 x 4 tablets over a 48-hr period or chloroquine (n = 90) given as four tablets (one tablet = 150 mg of chloroquine base) initially, followed by two tablets each at 6-8, 24, and 48 hr. Due to a death in the chloroquine group and a decrease in the chloroquine cure rate to < 50% (based on the blinded overall cure rate at that time), recruitment was terminated prematurely. CGP 56697 showed a superior 28-day cure rate (95.4% versus 19.7%; P < 0.001), time to parasite clearance (median = 36 versus 60 hr; P < 0.001), and resolution of fever (median = 18 versus 27 hr; P = 0.0456). This drug provides a safe, effective, and rapid therapy for the treatment of acute uncomplicated P. falciparum malaria.

The use and safety of non-allopathic Indian medicines.

Non-allopathic Indian medicines, referred to elsewhere in the world as complementary and alternative medicine have gathered increasing recognition in recent years with regard to both treatment options and health hazards. Ayurveda, Siddha, Unani and homeopathy are practiced in India as non-allopathic systems. These systems comprise a wide range of therapeutic approaches that include diet, herbs, metals, minerals, precious stones and their combinations as well as non-drug therapies. Ayurveda is the oldest system of medicine in the world and by far the most commonly practiced form of non-allopathic medicine in India, particularly in rural India, where 70% of the population lives. The difference between modern medicine and these systems stems from the fact that the knowledge base of many of the above systems, unlike Western medicine, is based on years of experience, observations, empiricism and intuition and has been handed down generations both through word of mouth and treatises. The focus on non-allopathic systems of medicine in India can be attributed to various causes including a need to revive a rich tradition, the dependency of 80% of the country's population on these drugs, their easy availability, increasing worldwide use of these medicines, the lack of focused concerted scientific research and the abuse of these systems by quacks. Elsewhere, the increasing use of herbal products worldwide and the growth of the herbal product industry has led to increasing concern regarding their safety. The challenges in these non-allopathic systems relate to the patient, physician, regulatory authorities, the abuse/misuse of these medicines, quality and purity issues. Safety monitoring is mandated by a changing ecological environment, the use of insecticides, new manufacturing techniques, an as yet unregulated pharmaceutical industry, the availability of combinations of herbs over the counter and not mentioned in ancient Ayurvedic texts, and the need to look at the active principles of these medicines as potential chemotherapeutic agents. The Indian traditional medicine industry has come a long way from the times when it was considered unnecessary to test these formulations prior to use, to the introduction of Good Manufacturing Practice guidelines for the industry. However, we still have a long way to go. The conflict between the traditional practitioners and the purists demanding evidence of safety and efficacy needs to be addressed. There is an urgent need for the practitioners of the allopathic and non-allopathic systems to work together to optimise the risk-benefit profile of these medicines.

Efficacy of a 14-day primaquine regimen in preventing relapses in patients with Plasmodium vivax malaria in Mumbai, India.

We studied the antirelapse efficacy of a supervised 14-d 15 mg/d regimen of primaquine therapy (n = 131) compared with no antirelapse therapy (n = 142) in 273 patients with confirmed Plasmodium vivax malaria in Mumbai, India, between July 1998 and April 2000. There were 6/131 (4.6%) recurrences in patients given primaquine compared with 13/142 (9.2%) in those not given antirelapse therapy. In the 14-d primaquine group, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) genotyping analysis of pre- and post-treatment blood samples was done for the 6 patients who had a recurrence of parasitaemia and the results gave a true relapse rate of 2.29% (3/131), 2 samples were classified as reinfections and 1 sample did not amplify. Our results indicate probable resistance to the 14-d regimen of primaquine for the first time in India and illustrate the need to (i) monitor patients given this regimen and (ii) carry out comparative studies between primaquine and new drugs such as tafenoquine and bulaquine for preventing relapses.

Analysis of a clinically important interaction between phenytoin and Shankhapushpi, an Ayurvedic preparation.

During the course of routine plasma drug level monitoring an unexpected loss of seizure control and reduction in plasma phenytoin levels was noticed in two patients who were also taking 'Shankhapushpi' (SRC), an Ayurvedic preparation. Therefore, the present study was undertaken in rats to investigate any SRC-phenytoin interaction from both pharmacokinetic (serum levels) and pharmacodynamic (electroshock seizure prevention) aspects. Single dose SRC and phenytoin (oral/i.p.) coadministration did not have any effect on plasma phenytoin levels but decreased the antiepileptic activity of phenytoin significantly. On multiple-dose coadministration, SRC reduced not only the antiepileptic activity of phenytoin but also lowered plasma phenytoin levels. SRC itself showed significant antiepileptic activity compared to placebo and is worth further investigation. However, the clinical combination of SRC with phenytoin is not advised.

Compliance monitoring in epileptic patients.

Poor patient compliance is one of the major causes of non responsiveness to antiepileptic drug therapy. Compliance is mostly assessed by self reporting, pill counting and plasma drug level estimation. However, none of them is fool proof. Subtherapeutic plasma drug levels can be due to poor compliance or need for higher dosage. Therefore, in the present study, 20 adult non responsive epileptic patients showing subtherapeutic plasma phenytoin levels inspite of receiving standard phenytoin therapy and history of good compliance were admitted in the clinical pharmacology ward and received supervised drug treatment for five days after which plasma phenytoin levels in 14 patients increased to therapeutic range. All except one (i.e. 9 out of 10) patients showing phenytoin levels < 5 ug/ml inspite of phenytoin dosage of > 300 mg/d and history of good compliance were found to be noncompliant. Hence adult patient receiving greater than or equal to 300 mg/day phenytion and showing phenytoin levels less than or equal to 5 ug/ml should be investigated for possible noncompliance before altering their dosage schedules.

Need for 25 mg tablets of phenytoin.

Phenytoin is widely used for the treatment of generalized tonic clonic and partial seizures. Monitoring of serum phenytoin levels is essential to optimize therapy. Of 320 patients monitored, 190 patients whose seizures were uncontrolled were followed up before and after dosage adjustment was carried out. Plasma phenytoin estimation was done by HPLC method. Of all the patients receiving the drug, 20% and 8% of patients were finally on dosages requiring 50 and 25 mg fraction administration respectively. Administration of 100 mg fractions resulted in either loss of seizure control or toxicity. This emphasizes the need for providing tablets of 25 mg strength, presently not available in this country.

Diagnostic and prognostic utility of rapid strip (OptiMal and Paracheck) versus conventional smear microscopy in adult patients of acute, uncomplicated P. falciparum malaria in Mumbai, India.

OBJECTIVES: The present study compared the diagnostic and prognostic utility of two rapid tests the (Paracheck and OptiMal) versus conventional smear microscopy. METHODS: Using two independent microscopists we carried out the three tests in 31 adult cases of smear positive, acute, uncomplicated Plasmodium falciparum malaria. All three tests were done pretreatment, and on Days 8, 15 and 29. RESULTS: Compared to microscopy, the Paracheck had a sensitivity of 100%, while the OptiMal had a sensitivity of 83.7%. The lower sensitivity of OptiMal resulted from misidentification by both microscopists of 6/31 cases as Plasmodium vivax. As a follow up tool, the OptiMal was better than Paracheck, due to the earlier disappearance of the parasite LDH. Also in the Paracheck, between microscopists, there was a significant difference in reading the tests, on Days 8 and 15. CONCLUSION: Our study reiterates, the continued utility of conventional smear microscopy.

Effect of gugulipid on bioavailability of diltiazem and propranolol.

The effect of single oral dose of 1 gm gugulipid was studied on bioavailability of single oral dose of propranolol (40 mg) and diltiazem (60 mg) in 10 and 7 normal healthy male volunteers respectively. It was a randomised within group crossover study. Blood samples were collected at hourly intervals upto 8 hrs. Gugulipid significantly reduced (P < .01) peak plasma concentration (Cmax) and area under curve (AUC 0-8 hrs) of both the drugs in normal volunteers. Such interaction in patients receiving propanolol or diltiazem with gugulipid may lead to diminished efficacy or nonresponsiveness due to significant reduction in bioavailability.

Relapse pattern of Plasmodium vivax in Mumbai: a study of 283 cases of vivax malaria.

OBJECTIVES: To analyze the relapse pattern of Plasmodium vivax in the city of Mumbai. METHODS: 283 cases of smear positive vivax malaria were treated with full dose (25 mg/kg) chloroquine and were asked to follow up for at least one year. None of the patients received primaquine. RESULTS: Of the 150 cases who followed up for at least one year, 19 relapsed, 17/19 relapsed within the first 6 months; indicating that the relapse pattern in the city is predominantly of the tropical or Chesson strain type. CONCLUSIONS: Vivax malaria patients should be monitored for at least six months. Those who do relapse should receive treatment with full dose chloroquine and 14 days of primaquine treatment.

A cost-effectiveness analysis of three antimalarial treatments for acute, uncomplicated Plasmodium falciparum malaria in Mumbai, India.

BACKGROUND: Malaria is a major public health problem representing 2.3% of the overall global disease burden. The cost of treatment of malaria continues to rise as older drugs and insecticides become less effective and are replaced by more effective, but also more expensive products. METHODS: A post-hoc pharmacoeconomic analysis (direct and indirect costs only) of three antimalarials, chloroquine, mefloquine and co-artemether, was carried out to address the problem of switch to a more expensive first-line antimalarial in the face of growing chloroquine resistance. RESULTS: From the perspective of a large public hospital, it was seen that in an area of high grade chloroquine resistance, the total expenditure on patients who fail chloroquine would exceed the excess expenditure on mefloquine when the RII + RIII resistance exceeded 9%. CONCLUSIONS: Switch to a more expensive drug like mefloquine as a first-line option would be cost-effective when the moderate-severe chloroquine resistance exceeded 9%.

Antirelapse Efficacy of Various Primaquine Regimens for Plasmodium vivax.

Background. Efficacy of standard dose of primaquine (PQ) as antirelapse for P. vivax has decreased. We aimed to assess efficacy of different PQ regimens. Methods. It was an open label, randomized, controlled, parallel group, assessor blind study comparing antirelapse efficacy of 3 PQ regimens (B = 15 mg/day × 14 days, C = 30 mg/day × 7 days, and D = 30 mg/day × 14 days) with no PQ group (A) in P. vivax patients. Paired primary and recurrence samples were subjected to 3 methods: (i) month of recurrence and genotyping, (ii) by PCR-RFLP, and (iii) PCR sequencing, to differentiate relapse and reinfection. The rates of recurrence relapse and reinfection were compared. Methods were compared for concordance between them. Results. The recurrence rate was 16.39%, 8.07%, 10.07%, and 6.62% in groups A, B, C, and D, respectively (P = 0.004). The relapse rate was 6.89%, 1.55%, 4%, and 3.85% as per the month of recurrence; 8.2%, 2%, 4.58%, and 3.68% (P = 0.007) as per PCR-RFLP; and 2.73%, 1.47%, 1.55%, and 1.53% as per PCR sequencing for groups A, B, C, and D, respectively. The concordance between methods was low, 45%. Conclusion. The higher recurrence rate in no PQ as compared to PQ groups documents PQ antirelapse activity. Regimens tested were safe. However, probable resistance to PQ warrants continuous monitoring and low concordance and limitations in the methods warrant caution in interpreting.