Safety of daily co-trimoxazole in pregnancy in an area of changing malaria epidemiology: a phase 3b randomized controlled clinical trial

Intermittent preventive treatment regimens for malaria in HIV-positive pregnant women

BACKGROUND

Malaria and HIV infection overlap geographically in sub-Saharan Africa and share risk factors. HIV infection increases malaria's severity, especially in pregnant women. The World Health Organization (WHO) recommends intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) for pregnant women living in areas of stable malaria transmission. However, HIV-positive women on daily cotrimoxazole prophylaxis (recommended for prevention of opportunistic infections in people with HIV) cannot receive SP due to adverse drug interactions, so malaria prevention in this vulnerable population currently relies on daily cotrimoxazole prophylaxis alone. This review is based on a new protocol and provides an update to the 2011 Cochrane Review that evaluated alternative drugs for IPTp to prevent malaria in HIV-positive women.

OBJECTIVES

To compare the safety and efficacy of intermittent preventive treatment regimens for malaria prevention in HIV-positive pregnant women.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases, and two trial registries to 31 January 2024. To identify relevant additional studies or unpublished work, we checked references and contacted study authors and other researchers working on malaria and HIV.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing any intermittent preventive treatment regimen for preventing malaria in HIV-positive pregnant women against daily cotrimoxazole prophylaxis alone, placebo, current or previous standard of care, or combinations of these options. By 'standard of care' we refer to the country's recommended drug regimen to prevent malaria in pregnancy among HIV-positive women, or the treatment that a trial's research team considered to be the standard of care.

DATA COLLECTION AND ANALYSIS

Review authors, in pairs, independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias in included trials, and extracted data. We contacted trial authors when additional information was required. We presented dichotomous outcomes using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes as mean differences (MDs). We presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of the evidence using the GRADE approach for what we considered to be the main comparisons and outcomes.

MAIN RESULTS

We included 14 RCTs, with a total of 4976 HIV-positive pregnant women initially randomized. All trials assessed the efficacy and safety of one antimalarial used as IPTp (mefloquine, dihydroartemisinin/piperaquine, SP, or azithromycin) with or without daily cotrimoxazole, compared to daily cotrimoxazole alone, placebo, or a standard of care regimen. We grouped the trials into nine comparisons. Our main comparison evaluated the current standard of care (daily cotrimoxazole) with another drug regimen (mefloquine or dihydroartemisinin/piperaquine) versus daily cotrimoxazole with or without placebo. In this comparison, two trials evaluated mefloquine and three evaluated dihydroartemisinin/piperaquine. We conducted meta-analyses that included trials evaluating dihydroartemisinin/piperaquine plus cotrimoxazole, and trials that evaluated mefloquine plus cotrimoxazole, as we considered there to be no qualitative or quantitative heterogeneity among trials for most outcomes. We considered drug-related adverse events and HIV-related outcomes to be drug-specific. Daily cotrimoxazole prophylaxis plus another drug regimen (mefloquine or dihydroartemisinin/piperaquine) probably results in lower risk of maternal peripheral parasitaemia at delivery (RR 0.62, 95% CI 0.41 to 0.95; 2406 participants, 5 trials; moderate-certainty evidence). It results in little or no difference in maternal anaemia cases at delivery (RR 0.98, 95% CI 0.90 to 1.07; 2417 participants, 3 trials; high-certainty evidence). It probably results in a decrease in placental malaria measured by blood smear (RR 0.54, 95% CI 0.31 to 0.93; 1337 participants, 3 trials; moderate-certainty evidence), and probably results in little or no difference in low birth weight (RR 1.16, 95% CI 0.95 to 1.41; 2915 participants, 5 trials; moderate-certainty evidence). There is insufficient evidence to ascertain whether daily cotrimoxazole prophylaxis plus another drug regimen affects the risk of cord blood parasitaemia (RR 0.27, 95% CI 0.04 to 1.64; 2696 participants, 5 trials; very low-certainty evidence). Daily cotrimoxazole prophylaxis plus another drug regimen probably results in little or no difference in foetal loss (RR 1.03, 95% CI 0.73 to 1.46; 2957 participants, 5 trials; moderate-certainty evidence), and may result in little or no difference in neonatal mortality (RR 1.21, 95% CI 0.68 to 2.14; 2706 participants, 4 trials; low-certainty evidence). Due to the probability of an increased risk of mother-to-child HIV transmission and some adverse drug effects noted with mefloquine, we also looked at the results for dihydroartemisinin/piperaquine specifically. Dihydroartemisinin/piperaquine plus daily contrimoxazole probably results in little to no difference in maternal peripheral parasitaemia (RR 0.59, 95% CI 0.31 to 1.11; 1517 participants, 3 trials; moderate-certainty evidence) or anaemia at delivery (RR 0.95, 95% CI 0.82 to 1.10; 1454 participants, 2 trials; moderate-certainty evidence), but leads to fewer women having placental malaria when measured by histopathologic analysis (RR 0.67, 95% CI 0.50 to 0.90; 1570 participants, 3 trials; high-certainty evidence). The addition of dihydroartemisinin/piperaquine to daily cotrimoxazole probably made little to no difference to rates of low birth weight (RR 1.13, 95% CI 0.87 to 1.48; 1695 participants, 3 trials), foetal loss (RR 1.14, 95% CI 0.68 to 1.90; 1610 participants, 3 trials), or neonatal mortality (RR 1.03, 95% CI 0.39 to 2.72; 1467 participants, 2 trials) (all moderate-certainty evidence). We found low-certainty evidence of no increased risk of gastrointestinal drug-related adverse events (RR 1.42, 95% CI 0.51 to 3.98; 1447 participants, 2 trials) or mother-to-child HIV transmission (RR 1.54, 95% CI 0.26 to 9.19; 1063 participants, 2 trials).

AUTHORS' CONCLUSIONS

Dihydroartemisinin/piperaquine and mefloquine added to daily cotrimoxazole seem to be efficacious in preventing malaria infection in HIV-positive pregnant women compared to daily cotrimoxazole alone. However, increased risk of HIV transmission to the foetus and poor drug tolerability may be barriers to implementation of mefloquine in practice. In contrast, the evidence suggests that dihydroartemisinin/piperaquine does not increase the risk of HIV mother-to-child transmission and is well tolerated.

Impact of prophylactic antimalarials in pregnant women living with Human Immunodeficiency Virus on birth outcomes in Botswana

OBJECTIVES

Until late 2015, Botswana recommended preventive treatment for pregnant women in malarial regions with chloroquine and proguanil (CP). The guideline change provided an opportunity to evaluate CP and adverse birth outcomes.

METHODS

The Tsepamo Study performed birth outcomes surveillance at large delivery centres throughout Botswana. We evaluated adverse birth outcomes from 2015 to 2017 at three hospitals where 93% of CP use was recorded. Outcomes included neonatal death (NND), small for gestational age (SGA), very SGA, stillbirth (SB), preterm delivery (PTD) and very PTD. Logistic regression analysis (unadjusted and adjusted) was conducted for each adverse birth outcome.

RESULTS

During the study period, 5883 (26%) of 23,033 deliveries were exposed to CP, with the majority (65%) in the most malaria-endemic region. At this site, there was a trend or an association between CP use and reduction of three adverse birth outcomes: PTD (aOR 0.85, 95% CI 0.76-0.96), vPTD (aOR 0.83, 95% CI 0.68-1.01) and NND (aOR 0.65, 95% CI 0.42-1.00). However, at the least malaria-endemic site, the association was in the opposite direction for SB (aOR 1.54, 95% CI 1.08-2.22), SGA (aOR 1.24, 95% CI 1.06-1.44) and vSGA (aOR 1.42, 95% CI 1.14-1.77). The association between CP and reduced PTD was present among women without HIV (aOR 0.77, 95% CI 0.67-0.89) but not among women with HIV (aOR 1.09, 95% CI 0.78-1.35).

CONCLUSIONS

Antimalarial prophylaxis was associated with improved birth outcomes in the most malaria-endemic region of Botswana, but not elsewhere. This finding supports current WHO guidance to use prophylaxis strategies among pregnant women in highly malaria-endemic regions. Further studies of the risks and benefits of specific antimalarial regimens in pregnancy are warranted, particularly in areas with lower incidence of malaria.

Drugs for Intermittent Preventive Treatment of Malaria in Pregnancy: Current Knowledge and Way Forward

Malaria infection during pregnancy is an important driver of maternal and neonatal health in endemic countries. Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for malaria prevention at each scheduled antenatal care visit, starting at the second trimester, in areas of high and moderate transmission. However, the increased resistance to SP in some endemic areas challenges its effectiveness. Furthermore, SP is contraindicated in the first trimester of pregnancy and in HIV-infected women on co-trimoxazole prophylaxis due to potential drug–drug interactions. Thus, in recent last decades, several studies evaluated alternative drugs that could be used for IPTp. A comprehensive literature review was conducted to summarize the evidence on the efficacy and safety of antimalarial drugs being evaluated for IPTp. Chloroquine, amodiaquine, mefloquine and azithromycin as IPTp have proven to be worse tolerated than SP. Mefloquine was found to increase the risk of mother-to-child transmission of HIV. Dihydroartemisin-piperaquine currently constitutes the most promising IPTp drug alternative; it reduced the prevalence of malaria infection, and placental and clinical malaria in studies among HIV-uninfected women, and it is currently being tested in HIV-infected women. Research on effective antimalarial drugs that can be safely administered for prevention to pregnant women should be prioritized. Malaria prevention in the first trimester of gestation and tailored interventions for HIV-infected women remain key research gaps to be addressed.

Effectiveness of antenatal intermittent preventive treatment for malaria with sulphadoxine-pyrimethamine on peripartum outcomes

Background

Following the World Health Organization (WHO) recommendations for 4-weekly antenatal intermittent preventive treatment of malaria in pregnancy using sulphadoxine-pyrimethamine (IPTp-SP), there is a need to evaluate the drug performance in order to determine their effectiveness as tools in malaria control policy.

Objectives

To determine prevalence of cord blood malaria, compliance gap and adverse pregnancy outcomes (anaemia, preterm delivery, spontaneous abortion, intra-uterine foetal death and low birth weight) among antenatal IPTp-SP users compared with non-users.

Methods

A cross-sectional analytical study was conducted among consenting 390 participants who were administered a questionnaire, and paired blood samples were collected from the venous blood of participants and neonatal cord immediately after delivery. The participants were categorised as IPTp-SP users and non-users. Adverse pregnancy outcomes were assessed. Neonatal birth weights were also measured within 1 h after delivery. Malaria parasitaemia and anaemia were analysed using standard parasitological and haematological methods of examination. Data were analysed using SPSS version 25 for Windows and p-value of < 0.05 considered significant.

Results

Of 390 women, 336 (86.2%) were IPTp-SP users, while 54 (13.8%) were non-users. The compliance gap was 13.8%. Malaria parasitemia in pregnant women (21.7% versus 53.7%; p < 0.001) and their babies (12.2% versus 25.4%; p = 0.002) were observed for IPTp-SP users and non-users, respectively. The prevalence of maternal anaemia was 27(8.0%) in IPTp-SP users and 5 (9.3%) in non-users (p = 0.789). Mean parasite density was reduced in IPTp-SP users than in non-users (p < 0.001). Correlation of birth weight according to their sex showed a weak correlation [correlation coefficient (r) = 0.027; p = 0.736]. Pregnant women with preterm delivery, spontaneous abortion, intra-uterine foetal death, and low birth weight were significantly lower (p < 0.001, for all) in IPTp-SP users compared with non-users.

Conclusion

Although the compliance gap was low, IPTp-SP users had significantly better pregnancy and foetal outcomes compared with non-users. Efforts should be intensified towards achieving total compliance in IPTp-SP usage by pregnant women.

Selected Derivatives of Erythromycin B-In Silico and Anti-Malarial Studies

Erythromycin A is an established anti-bacterial agent against Gram-positive bacteria, but it is unstable to acid. This led to an evaluation of erythromycin B and its derivatives because these have improved acid stability. These compounds were investigated for their anti-malarial activities, by their in silico molecular docking into segments of the exit tunnel of the apicoplast ribosome from Plasmodium falciparum. This is believed to be the target of the erythromycin A derivative, azithromycin, which has mild anti-malarial activity. The erythromycin B derivatives were evaluated on the multi-drug (chloroquine, pyrimethamine, and sulfadoxine)-resistant strain K1 of P. falciparum for asexual growth inhibition on asynchronous culture. The erythromycin B derivatives were identified as active in vitro inhibitors of asexual growth of P. falciparum with low micro-molar IC₅₀ values after a 72 h cycle. 5-Desosaminyl erythronolide B ethyl succinate showed low IC₅₀ of 68.6 µM, d-erythromycin B 86.8 µM, and erythromycin B 9-oxime 146.0 µM on the multi-drug-resistant K1 of P. falciparum. Based on the molecular docking, it seems that a small number of favourable interactions or the presence of unfavourable interactions of investigated derivatives of erythromycin B with in silico constructed segment from the exit tunnel from the apicoplast of P. falciparum is the reason for their weak in vitro anti-malarial activities.

Cotrimoxazole versus sulfadoxine-pyrimethamine for intermittent preventive treatment of malaria in HIV-infected pregnant women in Bangui, Central African Republic: A pragmatic randomised controlled trial

OBJECTIVE

The main objective of the MACOMBA (Maternity and Control of Malaria-HIV co-infection in Bangui) trial was to show that cotrimoxazole (CTX) is more effective than sulphadoxine-pyremethamine-IPTp (IPTp-SP) to prevent placental malaria infection (primary end point) among HIV-positive pregnant women with a CD4+ count ≥350 cells/mm³ in Bangui, CAR.

METHODS

MACOMBA is a multicentre, open-label randomised trial conducted in four maternity hospitals in Bangui. Between 2013 and 2017, 193 women were randomised and 112 (59 and 53 in CTX and IPTp-SP arms, respectively) were assessed for placental infection defined by microscopic parasitaemia or PCR.

RESULTS

Thirteen women had a placental infection: five in the CTX arm (one by microscopic placental parasitaemia and four by PCR) and eight by PCR in the SP-IPTp (8.5% vs. 15.1%, p = 0.28). The percentage of newborns with low birthweight (<2500 g) did not differ statistically between the two arms. Self-reported compliance to CTX prophylaxis was good. There was a low overall rate of adverse events in both arms.

CONCLUSION

Although our results do not allow us to conclude that CTX is more effective, drug safety and good compliance among women with this treatment favour its widespread use among HIV-infected pregnant women, as currently recommended by WHO.

Safety of Antimicrobials During Pregnancy: A Systematic Review of Antimicrobials Considered for Treatment and Postexposure Prophylaxis of Plague

BACKGROUND

The safety profile of antimicrobials used during pregnancy is one important consideration in the decision on how to treat and provide postexposure prophylaxis (PEP) for plague during pregnancy.

METHODS

We searched 5 scientific literature databases for primary sources on the safety of 9 antimicrobials considered for plague during pregnancy (amikacin, gentamicin, plazomicin, streptomycin, tobramycin, chloramphenicol, doxycycline, sulfadiazine, and trimethoprim-sulfamethoxazole [TMP-SMX]) and abstracted data on maternal, pregnancy, and fetal/neonatal outcomes.

RESULTS

Of 13 052 articles identified, 66 studies (case-control, case series, cohort, and randomized studies) and 96 case reports were included, totaling 27 751 prenatal exposures to amikacin (n = 9), gentamicin (n = 345), plazomicin (n = 0), streptomycin (n = 285), tobramycin (n = 43), chloramphenicol (n = 246), doxycycline (n = 2351), sulfadiazine (n = 870), and TMP-SMX (n = 23 602). Hearing or vestibular deficits were reported in 18/121 (15%) children and 17/109 (16%) pregnant women following prenatal streptomycin exposure. First trimester chloramphenicol exposure was associated with an elevated risk of an undescended testis (odds ratio [OR] 5.9, 95% confidence interval [CI] 1.2-28.7). Doxycycline was associated with cardiovascular malformations (OR 2.4, 95% CI 1.2-4.7) in 1 study and spontaneous abortion (OR 2.8, 95% CI 1.9-4.1) in a separate study. First trimester exposure to TMP-SMX was associated with increased risk of neural tube defects (pooled OR 2.5, 95% CI 1.4-4.3), spontaneous abortion (OR 3.5, 95% CI 2.3-5.6), preterm birth (OR 1.5, 95% CI 1.1-2.1), and small for gestational age (OR 1.6, 95% CI 1.2-2.2). No other statistically significant associations were reported.

CONCLUSIONS

For most antimicrobials reviewed, adverse maternal/fetal/neonatal outcomes were not observed consistently. Prenatal exposure to streptomycin and TMP-SMX was associated with select birth defects in some studies. Based on limited data, chloramphenicol and doxycycline may be associated with adverse pregnancy or neonatal outcomes; however, more data are needed to confirm these associations. Antimicrobials should be used for treatment and PEP of plague during pregnancy; the choice of antimicrobials may be influenced by these data as well as information about the risks of plague during pregnancy.

Systematic review of statistical methods for safety data in malaria chemoprevention in pregnancy trials

BACKGROUND

Drug safety assessments in clinical trials present unique analytical challenges. Some of these include adjusting for individual follow-up time, repeated measurements of multiple outcomes and missing data among others. Furthermore, pre-specifying appropriate analysis becomes difficult as some safety endpoints are unexpected. Although existing guidelines such as CONSORT encourage thorough reporting of adverse events (AEs) in clinical trials, they provide limited details for safety data analysis. The limited guidelines may influence suboptimal analysis by failing to account for some analysis challenges above. A typical example where such challenges exist are trials of anti-malarial drugs for malaria prevention during pregnancy. Lack of proper standardized evaluation of the safety of antimalarial drugs has limited the ability to draw conclusions about safety. Therefore, a systematic review was conducted to establish the current practice in statistical analysis for preventive antimalarial drug safety in pregnancy.

METHODS

The search included five databases (PubMed, Embase, Scopus, Malaria in Pregnancy Library and Cochrane Central Register of Controlled Trials) to identify original English articles reporting Phase III randomized controlled trials (RCTs) on anti-malarial drugs for malaria prevention in pregnancy published from January 2010 to July 2019.

RESULTS

Eighteen trials were included in this review that collected multiple longitudinal safety outcomes including AEs. Statistical analysis and reporting of the safety outcomes in all the trials used descriptive statistics; proportions/counts (n = 18, 100%) and mean/median (n = 2, 11.1%). Results presentation included tabular (n = 16, 88.9%) and text description (n = 2, 11.1%). Univariate inferential methods were reported in most trials (n = 16, 88.9%); including Chi square/Fisher's exact test (n = 12, 66.7%), t test (n = 2, 11.1%) and Mann-Whitney/Wilcoxon test (n = 1, 5.6%). Multivariable methods, including Poisson and negative binomial were reported in few trials (n = 3, 16.7%). Assessment of a potential link between missing efficacy data and safety outcomes was not reported in any of the trials that reported efficacy missing data (n = 7, 38.9%).

CONCLUSION

The review demonstrated that statistical analysis of safety data in anti-malarial drugs for malarial chemoprevention in pregnancy RCTs is inadequate. The analyses insufficiently account for multiple safety outcomes potential dependence, follow-up time and informative missing data which can compromise anti-malarial drug safety evidence development, based on the available data.

Use of trimethoprim-sulfamethoxazole during pregnancy and risk of spontaneous abortion: a nested case control study

AIMS

Data available on the fetal safety of trimethoprim-sulfamethoxazole (TMP-SMX) exposure during pregnancy remains scarce and inconclusive. A previous study assessing the link between TMP-SMX exposure during pregnancy and the risk of spontaneous abortion (SA) did not control for protopathic bias and indication bias.

METHODS

We conducted a nested control study (n = 77 429 pregnancies including 7039 cases of SA and 70 390 controls) within the Quebec Pregnancy Cohort. For each case of SA, we selected 10 controls at the index date that were matched on gestational age and year of pregnancy. TMP-SMX exposure was defined as either having filled at least one prescription between the first day of gestation (1DG) and the index date, or as having filled a prescription before pregnancy but with a duration overlapping the 1DG (102 pregnancies exposed to TMP-SMX, including 25 cases of SA and 77 controls).

RESULTS

Adjusting for potential confounders, TMP-SMX exposure was associated with an increased risk of SA (AOR 2.94, 95% C 1.89-4.57, 25 exposed cases). Similar results were found after controlling for indication bias and protopathic bias.

CONCLUSION

Given that this drug is widely use in HIV patients to prevent opportunistic infections and malaria, there is an urgent need to identify potential data sources in Africa for analysis of early pregnancy exposure to TMP-SMX.

Prevention and control of malaria in pregnancy - new threats, new opportunities?

INTRODUCTION

Over 100 million women and their babies are at risk of malaria in pregnancy each year. Malaria prevention in pregnancy relies on long-lasting insecticidal nets (LLINs), and, in Africa, intermittent preventive treatment in pregnancy (IPTp). Increasing resistance of malaria parasites to sulfadoxine-pyrimethamine, the only drug endorsed for IPTp, and increasing mosquito resistance to pyrethroids used in LLINs, threaten the efficacy of these proven strategies, while operational challenges restrict their implementation in areas of great need. Areas Covered: This review summarizes strategies for malaria prevention in pregnancy (both currently used and those undergoing preclinical and clinical evaluation), primarily drawing on publications and study protocols from the last decade. Challenges associated with each strategy are discussed, including the particular problem of HIV and malaria in pregnancy, and areas of further research are highlighted. Expert Commentary: Alternative drugs for IPTp are needed. Dihydroartemisinin-piperaquine is particularly promising, but requires further evaluation, and might contribute to artemisinin resistance. Intermittent screening and treatment in pregnancy (ISTp) is an alternative to IPTp that could reduce unnecessary antenatal drug exposure and resistance risk, but it is not recommended with current, insensitive screening tests. Optimal strategies for areas of low or declining malaria transmission remain to be determined.

Antibiotics in malaria therapy: which antibiotics except tetracyclines and macrolides may be used against malaria?

Malaria, a parasite vector-borne disease, is one of the most significant health threats in tropical regions, despite the availability of individual chemoprophylaxis. Malaria chemoprophylaxis and chemotherapy remain a major area of research, and new drug molecules are constantly being developed before drug-resistant parasites strains emerge. The use of anti-malarial drugs is challenged by contra-indications, the level of resistance of Plasmodium falciparum in endemic areas, clinical tolerance and financial cost. New therapeutic approaches are currently needed to fight against this disease. Some antibiotics that have shown potential effects on malaria parasite have been recently studied in vitro or in vivo intensively. Two families, tetracyclines and macrolides and their derivatives have been particularly studied in recent years. However, other less well-known have been tested or are being used for malaria treatment. Some of these belong to older families, such as quinolones, co-trimoxazole or fusidic acid, while others are new drug molecules such as tigecycline. These emerging antibiotics could be used to prevent malaria in the future. In this review, the authors overview the use of antibiotics for malaria treatment.

Lack of effect of intermittent preventive treatment for malaria in pregnancy and intense drug resistance in western Uganda

Background

Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine–pyrimethamine (SP) is widely implemented in sub-Saharan Africa for the prevention of malaria in pregnancy and adverse birth outcomes. However, in areas of intense SP resistance, the efficacy of IPTp may be compromised.

Methods

A cross-sectional study among 915 delivering women (728 analysable live singleton deliveries) was conducted in Fort Portal, western Uganda, to assess associations of reported IPTp use, Plasmodium falciparum infection, maternal anaemia, low birth weight, and preterm delivery, and to estimate the degree of SP resistance as reflected by pfdhfr/pfdhps mutations.

Results

Plasmodium falciparum infection was detected by PCR in 8.9 % and by microscopy of placental blood samples in 4.0 %. Infection was significantly associated with stillbirth, early neonatal death, anaemia, low birth weight, and pre-term delivery. Eighty percent of the women had taken at least one dose of IPTp, and more than half had taken two doses. As compared to women without chemoprophylaxis against malaria, IPTp had no significant influence on the presence of P. falciparum infection (13.8 vs. 9.6 %, P = 0.31). Nor was it associated with reductions in anaemia, low birth weight or preterm delivery. P. falciparum with intense SP resistance (pfdhfr/pfdhps quintuple or sextuple mutations) were observed in 93 % (pfdhps 581G, 36 %), and the additional high resistance allele pfhdr 164L in 36 %.

Conclusions

In Fort Portal, Uganda, reported use of IPTp with SP does not provide an observable benefit. The molecular markers of P. falciparum indicate high grade SP resistance reaching the threshold set by WHO for the discontinuation of IPTp with SP. Alternative approaches for the prevention of malaria in pregnancy are urgently needed.

Antimalarial drugs for preventing malaria during pregnancy and the risk of low birth weight: a systematic review and meta-analysis of randomized and quasi-randomized trials

BACKGROUND

It is known that antimalarial drugs reduce the risk of low birth weight (LBW) in pregnant patients. However, a previous Cochrane review did not evaluate whether the level of antimalarial drug resistance could modify the protective effect of antimalarial drugs in this regard. In addition, no systematic review exists comparing current recommendations for malaria prevention during pregnancy to alternative regimens in Africa. Therefore, we conducted a comprehensive systematic review and meta-analysis to assess the efficacy of antimalarial drugs for malaria prevention during pregnancy in reducing the risk of LBW.

METHODS

We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) for articles published up to 21 November 2014, in English or French, and identified additional studies from reference lists. We included randomized and quasi-randomized studies reporting LBW as one of the outcomes. We extracted data and assessed the risk of bias in selected studies. All pooled analyses were based on a random effect model, and we used a funnel plot and trim and fill method to test and adjust for publication bias.

RESULTS

A total of 25 studies met the inclusion criteria (37,981 subjects). Compared to no use, all combined antimalarial drugs were associated with a 27% (RR 0.73, 95% CI 0.56-0.97, ten studies) reduction in the risk of LBW. The level of antimalarial drug resistance modified the protective effect of the antimalarial drug used for prevention of LBW during pregnancy. Sulfadoxine-pyrimethamine was not associated with a reduction in the risk of LBW in regions where the prevalence of the dihydropteroate synthase 540E mutation exceeds 50% (RR 0.99, 95% CI 0.80-1.22, three studies). The risk of LBW was similar when sulfadoxine-pyrimethamine was compared to mefloquine (RR 1.05, 95% CI 0.86-1.29, two studies).

CONCLUSION

Prophylactic antimalarial drugs and specifically sulfadoxine-pyrimethamine may no longer protect against the risk of LBW in areas of high-level resistance. In Africa, there are currently no suitable alternative drugs to replace sulfadoxine-pyrimethamine for malaria prevention during pregnancy.

The expanding role of co-trimoxazole in developing countries

Co-trimoxazole is an inexpensive, broad-spectrum antimicrobial drug that is widely used in developing countries. Before antiretroviral therapy (ART) scale-up, co-trimoxazole prophylaxis reduced morbidity and mortality in adults and children with HIV by preventing bacterial infections, diarrhoea, malaria, and Pneumocystis jirovecii pneumonia, despite high levels of microbial resistance. Co-trimoxazole prophylaxis reduces early mortality by 58% (95% CI 39-71) in adults starting ART. Co-trimoxazole provides ongoing protection against malaria and non-malaria infections after immune reconstitution in ART-treated individuals in sub-Saharan Africa, leading to a change in WHO guidelines, which now recommend long-term co-trimoxazole prophylaxis for adults and children in settings with a high prevalence of malaria or severe bacterial infections. Co-trimoxazole prophylaxis is recommended for HIV-exposed infants from age 4-6 weeks; however, the risks and benefits of co-trimoxazole during infancy are unclear. Co-trimoxazole prophylaxis reduces anaemia and improves growth in children with HIV, possibly by reducing inflammation, either through direct immunomodulatory activity or through effects on the intestinal microbiota leading to reduced microbial translocation. Ongoing trials are now assessing the ability of adjunctive co-trimoxazole to reduce mortality in children after severe anaemia or severe acute malnutrition. In this Review, we discuss the mechanisms of action, benefits and risks, and clinical trials of co-trimoxazole in developing countries.