Having the cake and eating it? Clofazimine boosts immunotherapy while limiting side effects

Combined immune checkpoint blockade (ICB) for cancer exhibits good efficacy in a subset of patients but also associates with immune-related adverse events. Xue et al. use an elegant drug screening strategy to identify the antimicrobial drug clofazimine as an agent that both potentiates ICB efficacy and decreases immune-related adverse events.

Safety and Efficacy of Clofazimine as an Alternative for Rifampicin in Mycobacterium avium Complex Pulmonary Disease Treatment: Outcomes of a Randomized Trial

BACKGROUND

Results of retrospective studies have suggested clofazimine as an alternative for rifampicin in the treatment of Mycobacterium avium complex pulmonary disease (MAC-PD).

RESEARCH QUESTION

Is a treatment regimen consisting of clofazimine-ethambutol-macrolide noninferior to the standard treatment regimen (rifampicin-ethambutol-macrolide) in the treatment of MAC-PD?

STUDY DESIGN AND METHODS

In this single-center, nonanonymized clinical trial, adult patients with MAC-PD were randomly assigned in a 1:1 ratio to receive rifampicin or clofazimine as adjuncts to an ethambutol-macrolide regimen. The primary outcome was sputum culture conversion following 6 months of treatment.

RESULTS

Forty patients were assigned to receive either rifampicin (n = 19) or clofazimine (n = 21) in addition to ethambutol and a macrolide. Following 6 months of treatment, both arms showed similar percentages of sputum culture conversion based on an intention-to-treat analysis: 58% (11 of 19) for rifampicin and 62% (13 of 21) for clofazimine. Study discontinuation, mainly due to adverse events, was equal in both arms (26% vs 33%). Based on an on-treatment analysis, sputum culture conversion following 6 months of treatment was 79% in both groups. In the clofazimine arm, diarrhea was more prevalent (76% vs 37%; P = .012), while arthralgia was more frequent in the rifampicin arm (37% vs 5%; P = .011). No difference in the frequency of corrected QT interval prolongation was seen between groups.

INTERPRETATION

A clofazimine-ethambutol-macrolide regimen showed similar results to the standard rifampicin-ethambutol-macrolide regimen and should be considered in the treatment of MAC-PD. The frequency of adverse events was similar in both arms, but their nature was different. Individual patient characteristics and possible drug-drug interactions should be taken into consideration when choosing an antibiotic regimen for MAC-PD.

CLINICAL TRIAL REGISTRATION

EudraCT; No.: 2015-003786-28; URL: https://eudract.ema.europa.eu.

Clofazimine-induced cutaneous hyperpigmentation as a source of stigma in the treatment of leprosy: A cross-sectional study

OBJECTIVES

Cutaneous hyperpigmentation is one of the main adverse effects encountered in patients undergoing leprosy treatment with multidrug therapy (WHO-MDT). This adverse effect has been described as intolerable and capable of contributing to social stigma. The objectives of this study were to quantify the variation in skin colour induced by clofazimine during and after treatment and to assess the related stigma.

METHODS

This observational cross-sectional study objectively measured skin colour in 51 patients by reading the individual typology angle (ITA°) with a spectrophotometer, followed by the application of the Stigma Scale of the Explanatory Model Interview Catalogue (EMIC).

RESULTS

Skin hyperpigmentation was observed in 100% of the individuals. They showed more negative ITA° values in lesion areas than non-lesion areas, particularly in sun-exposed regions. Clofazimine-induced cutaneous hyperpigmentation was not homogeneous and seemed to follow the lesion locations. The mean EMIC score was 18.8 points.

CONCLUSION

All patients presented skin hyperpigmentation caused by clofazimine, detectable through spectrophotometry. Hyperpigmentation strongly impacted the social domain, indicating the intersectionality of disease and skin colour stigma, contributing to the social isolation of these patients. Health authorities should consider the negative impact of clofazimine on treatment adherence.

Case Report: Borderline Lepromatous Leprosy Therapy Complicated by Type 1 Leprosy Reaction and Adverse Reactions with Dapsone and Clofazimine

Leprosy is a global health issue, causing long-term functional morbidity and stigma. Rapid diagnosis and appropriate treatment are important; however, early diagnosis is often challenging, especially in nonendemic areas. Here, we report a case of borderline lepromatous leprosy accompanied by dapsone-induced (neutropenia, anemia, and methemoglobinemia) and clofazimine-induced (skin discoloration and ichthyosis) side effects and type 1 leprosy reactions during administration of the multidrug therapy. The patient completely recovered without developing any deformities or visual impairment. To ensure early diagnosis and a favorable outcome, clinicians should be aware of the diminished sensation of skin lesions as a key physical finding and manage the drug toxicities and leprosy reactions appropriately in patients on multidrug therapy.

Pharmacokinetics and cardiac safety of clofazimine in children with rifampicin-resistant tuberculosis

Clofazimine is recommended for the treatment of rifampicin-resistant tuberculosis (RR-TB), but there is currently no verified dosing guideline for its use in children. There is only limited safety and no pharmacokinetic (PK) data available for children. We aimed to characterize clofazimine PK and its relationship with QT-interval prolongation in children. An observational cohort study of South African children <18 years old routinely treated for RR-TB with a clofazimine-containing regimen was analyzed. Clofazimine 100 mg gelatin capsules were given orally once daily (≥20 kg body weight), every second day (10 to <20 kg), or thrice weekly (<10 kg). PK sampling and electrocardiograms were completed pre-dose and at 1, 4, and 10 hours post-dose, and the population PK and Fridericia-corrected QT (QTcF) interval prolongation were characterized. Fifty-four children contributed both PK and QTcF data, with a median age (2.5th-97.5th centiles) of 3.3 (0.5-15.6) years; five children were living with HIV. Weekly area under the time-concentration curve at steady state was 79.1 (15.0-271) mg.h/L compared to an adult target of 60.9 (56.0-66.6) mg.h/L. Children living with HIV had four times higher clearance compared to those without. No child had a QTcF ≥500 ms. A linear concentration-QTcF relationship was found, with a drug effect of 0.05 (0.027, 0.075) ms/µg/L. In some of the first PK data in children, we found clofazimine exposure using an off-label dosing strategy was higher in children versus adults. Clofazimine concentrations were associated with an increase in QTcF, but severe prolongation was not observed. More data are required to inform dosing strategies in children.

Efficacy and safety of an innovative short-course regimen containing clofazimine for treatment of drug-susceptible tuberculosis: a clinical trial

In preclinical studies, a new antituberculosis drug regimen markedly reduced the time required to achieve relapse-free cure. This study aimed to preliminarily evaluate the efficacy and safety of this four-month regimen, consisting of clofazimine, prothionamide, pyrazinamide and ethambutol, with a standard six-month regimen in patients with drug-susceptible tuberculosis. An open-label pilot randomized clinical trial was conducted among the patients with newly diagnosed bacteriologically-confirmed pulmonary tuberculosis. The primary efficacy end-point was sputum culture negative conversion. Totally, 93 patients were included in the modified intention-to-treat population. The rates of sputum culture conversion were 65.2% (30/46) and 87.2% (41/47) for short-course and standard regimen group, respectively. There was no difference on two-month culture conversion rates, time to culture conversion, nor early bactericidal activity (P > 0.05). However, patients on short-course regimen were observed with lower rates of radiological improvement or recovery and sustained treatment success, which was mainly attributed to higher percent of patients permanently changed assigned regimen (32.1% vs. 12.3%, P = 0.012). The main cause for it was drug-induced hepatitis (16/17). Although lowering the dose of prothionamide was approved, the alternative option of changing assigned regimen was chosen in this study. While in per-protocol population, sputum culture conversion rates were 87.0% (20/23) and 94.4% (34/36) for the respective groups. Overall, the short-course regimen appeared to have inferior efficacy and higher incidence of hepatitis but desired efficacy in per-protocol population. It provides the first proof-of-concept in humans of the capacity of the short-course approach to identify drug regimens that can shorten the treatment time for tuberculosis.

Evaluating newly approved drugs in combination regimens for multidrug-resistant tuberculosis with fluoroquinolone resistance (endTB-Q): study protocol for a multi-country randomized controlled trial

BACKGROUND

Treatment for fluoroquinolone-resistant multidrug-resistant/rifampicin-resistant tuberculosis (pre-XDR TB) often lasts longer than treatment for less resistant strains, yields worse efficacy results, and causes substantial toxicity. The newer anti-tuberculosis drugs, bedaquiline and delamanid, and repurposed drugs clofazimine and linezolid, show great promise for combination in shorter, less-toxic, and effective regimens. To date, there has been no randomized, internally and concurrently controlled trial of a shorter, all-oral regimen comprising these newer and repurposed drugs sufficiently powered to produce results for pre-XDR TB patients.

METHODS

endTB-Q is a phase III, multi-country, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of a treatment strategy for patients with pre-XDR TB. Study participants are randomized 2:1 to experimental or control arms, respectively. The experimental arm contains bedaquiline, linezolid, clofazimine, and delamanid. The control comprises the contemporaneous WHO standard of care for pre-XDR TB. Experimental arm duration is determined by a composite of smear microscopy and chest radiographic imaging at baseline and re-evaluated at 6 months using sputum culture results: participants with less extensive disease receive 6 months and participants with more extensive disease receive 9 months of treatment. Randomization is stratified by country and by participant extent-of-TB-disease phenotype defined according to screening/baseline characteristics. Study participation lasts up to 104 weeks post randomization. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 324 participants across 2 arms affords at least 80% power to show the non-inferiority, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per-protocol populations.

DISCUSSION

This internally controlled study of shortened treatment for pre-XDR TB will provide urgently needed data and evidence for clinical and policy decision-making around the treatment of pre-XDR TB with a four-drug, all-oral, shortened regimen.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT03896685. Registered on 1 April 2018; the record was last updated for study protocol version 4.3 on 17 March 2023.

Cotreatment With Clofazimine and Rapamycin Eliminates Drug-Resistant Tuberculosis by Inducing Polyfunctional Central Memory T-Cell Responses

Mycobacterium tuberculosis, the causative agent of tuberculosis, is acquiring drug resistance at a faster rate than the discovery of new antibiotics. Therefore, alternate therapies that can limit the drug resistance and disease recurrence are urgently needed. Emerging evidence indicates that combined treatment with antibiotics and an immunomodulator provides superior treatment efficacy. Clofazimine (CFZ) enhances the generation of T central memory (TCM) cells by blocking the Kv1.3+ potassium channels. Rapamycin (RAPA) facilitates M. tuberculosis clearance by inducing autophagy. In this study, we observed that cotreatment with CFZ and RAPA potently eliminates both multiple and extensively drug-resistant (MDR and XDR) clinical isolates of M. tuberculosis in a mouse model by inducing robust T-cell memory and polyfunctional TCM responses. Furthermore, cotreatment reduces the expression of latency-associated genes of M. tuberculosis in human macrophages. Therefore, CFZ and RAPA cotherapy holds promise for treating patients infected with MDR and XDR strains of M. tuberculosis.

Effects of Bedaquiline Combined with Fluoroquinolone and/or Clofazimine on QT Interval in Patients with Multidrug-Resistant Tuberculosis: a Retrospective Study

With the application of bedaquiline (Bdq), the success rate of multidrug-resistant tuberculosis (MDR-TB) treatment has been significantly improved; however, the cardiac safety of the patients during treatment cannot be ignored. Hence, this study compared the effects of bedaquiline alone and bedaquiline combined with fluoroquinolones (FQs) and/or clofazimine (CFZ) on the QT interval. This single-center retrospective cohort study analyzed the clinical data of MDR-TB patients treated with bedaquiline for 24 weeks from January 2020 to May 2021 in Xi'an Chest Hospital and compared the changes in QTcF between the two groups. Eighty-five patients were included in the study and grouped by types of anti-TB drugs affecting the QT interval they used. Group A included bedaquiline (n = 33), and group B included bedaquiline in combination with fluoroquinolones and/or clofazimine (n = 52). Out of patients with available corrected QT interval by Fridericia's formula (QTcF) data, 2.4% (2/85) experienced a postbaseline QTcF of ≥500 ms, and 24.7% (21/85) had at least one change of QTcF of ≥60 ms from baseline. In group A, 9.1% (3/33) had at least one ΔQTcF of >60 ms, as did 34.6% (18/52) of group B. Multivariate Cox regression analysis showed that the adjusted risk of QT prolongation was 4.82 times higher in group B (95% confidence interval [CI], 1.406 to 16.488). Bedaquiline combined with other anti-TB drugs affecting QT interval significantly increased the incidence of grade 3 or 4 QT prolongation; however, no serious ventricular arrhythmia and permanent drug withdrawal occurred. The use of bedaquiline combined with fluoroquinolone and/or clofazimine is an independent risk factor affecting QT interval. IMPORTANCE Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis. The emergence of MDR-TB is caused by an organism that is resistant to at least isoniazid and rifampin and is currently considered the major challenge for the global control of TB. Bedaquiline is the first new TB drug in 50 years with a unique mechanism of action, strong anti-M. tuberculosis activity. Yet unexplained excess deaths in the bedaquiline arms have been found in some phase II clinical trials; thus, the FDA has issued a "boxed warning." However, the cardiac safety of the patients during treatment cannot be ignored. Accordingly, further investigations are needed to establish whether bedaquiline combined with clofazimine, fluoroquinolones, or anti-TB drugs affecting the QT interval in a long-course or short-course treatment increases the risk of QT prolongation.

Seventy years of evidence on the efficacy and safety of drugs for treating leprosy: a network meta-analysis

OBJECTIVE

The World Health Organization (WHO) recommends multidrug therapy (MDT) with rifampicin, dapsone, and clofazimine for treating leprosy, which is based on very low-quality evidence. Here, we performed a network meta-analysis (NMA) to produce quantitative evidence to strengthen current WHO recommendations.

METHOD

All studies were obtained from Embase and PubMed from the date of establishment to October 9, 2021. Data were synthesized with frequentist random-effects network meta-analyses. Outcomes were assessed using odds ratios (ORs), 95% confidence intervals (95% CIs), and P score.

RESULTS

Sixty controlled clinical trials and 9256 patients were included. MDT was effective (range of OR: 1.06-1255584.25) for treating leprosy and multibacillary leprosy. Six treatments (Range of OR: 1.199-4.50) were more effective than MDT. Clofazimine (P score=0.9141) and dapsone+rifampicin (P score=0.8785) were effective for treating type 2 leprosy reaction. There were no significant differences in the safety of any of the tested drug regimens.

CONCLUSIONS

The WHO MDT is effective for treating leprosy and multibacillary leprosy, but it may not be effective enough. Pefloxacin and ofloxacin may be good adjunct drugs for increasing MDT efficacy. Clofazimine and dapsone+rifampicin can be used in the treatment of a type 2 leprosy reaction. Single-drug regimens are not efficient enough to treat leprosy, multibacillary leprosy, or a type 2 leprosy reaction.

AVAILABILITY OF DATA AND MATERIALS

All data generated or analyzed during this study are included in this published article [and its supplementary information files].

Assessment of multidrug-resistant tuberculosis patient's skin drug reaction in Zanzibar: A certain causal relationship with Clofazimine

Drug-resistant tuberculosis (DR-TB) is a serious public health of concern. We present the management of multidrug-resistant (MDR)-TB with skin reaction in Zanzibar in a patient who had prior exposure to anti-TB drugs. The reaction developed 4 months later, following MDR-TB treatment, stopped when the drug was withdrawn, and reappeared when reintroduced. Close monitoring is important in managing DR-TB cases, and an active DR-TB safety, monitoring, and management is required to detect, monitor, and manage adverse events timely.

Drug-associated adverse events in the treatment of multidrug-resistant tuberculosis: an individual patient data meta-analysis

BACKGROUND

Treatment of multidrug-resistant tuberculosis requires long-term therapy with a combination of multiple second-line drugs. These drugs are associated with numerous adverse events that can cause severe morbidity, such as deafness, and in some instances can lead to death. Our aim was to estimate the absolute and relative frequency of adverse events associated with different tuberculosis drugs to provide useful information for clinicians and tuberculosis programmes in selecting optimal treatment regimens.

METHODS

We did a meta-analysis using individual-level patient data that were obtained from studies that reported adverse events that resulted in permanent discontinuation of anti-tuberculosis medications. We used a database created for our previous meta-analysis of multidrug-resistant tuberculosis treatment and outcomes, for which we did a systematic review of literature published between Jan 1, 2009, and Aug 31, 2015 (updated April 15, 2016), and requested individual patient-level information from authors. We also considered for this analysis studies contributing patient-level data in response to a public call made by WHO in 2018. Meta-analysis for proportions and arm-based network meta-analysis were done to estimate the incidence of adverse events for each tuberculosis drug.

FINDINGS

58 studies were identified, including 50 studies from the updated individual patient data meta-analysis for multidrug-resistant tuberculosis treatment. 35 of these studies, with 9178 patients, were included in our analysis. Using meta-analysis of proportions, drugs with low risks of adverse event occurrence leading to permanent discontinuation included levofloxacin (1·3% [95% CI 0·3-5·0]), moxifloxacin (2·9% [1·6-5·0]), bedaquiline (1·7% [0·7-4·2]), and clofazimine (1·6% [0·5-5·3]). Relatively high incidence of adverse events leading to permanent discontinuation was seen with three second-line injectable drugs (amikacin: 10·2% [6·3-16·0]; kanamycin: 7·5% [4·6-11·9]; capreomycin: 8·2% [6·3-10·7]), aminosalicylic acid (11·6% [7·1-18·3]), and linezolid (14·1% [9·9-19·6]). Risk of bias in selection of studies was judged to be low because there were no important differences between included and excluded studies. Variability between studies was significant for most outcomes analysed.

INTERPRETATION

Fluoroquinolones, clofazimine, and bedaquiline had the lowest incidence of adverse events leading to permanent drug discontinuation, whereas second-line injectable drugs, aminosalicylic acid, and linezolid had the highest incidence. These results suggest that close monitoring of adverse events is important for patients being treated for multidrug-resistant tuberculosis. Our results also underscore the urgent need for safer and better-tolerated drugs to reduce morbidity from treatment itself for patients with multidrug-resistant tuberculosis.

FUNDING

Canadian Institutes of Health Research, Centers for Disease Control and Prevention (USA), American Thoracic Society, European Respiratory Society, and Infectious Diseases Society of America.

Safety and efficacy of hydroxyurea and eflornithine against most blood parasites Babesia and Theileria

BACKGROUND

The plenteous resistance to and undesirable consequences of the existing antipiroplasmic therapies have emphasized the urgent need for new chemotherapeutics and drug targets for both prophylaxis and chemotherapy. Hydroxyurea (HYD) is an antineoplastic agent with antitrypanosomal activity. Eflornithine (α-difluoro-methyl ornithine, DFMO) is the best choice therapy for the treatment of late-stage Gambian human African trypanosomiasis.

METHODS

In this study, the inhibitory and combination efficacy of HYD and DFMO with existing babesicidal drugs (diminazene aceturate (DA), atovaquone (ATV), and clofazimine (CLF)) deoxyribonucleotide in vitro against the multiplication of Babesia and Theileria. As well as, their chemotherapeutic effects were assessed on B. microti strain that infects rodents. The Cell Counting Kits-8 (CCK-8) test was used to examine their cytotoxicity on human foreskin fibroblast (HFF), mouse embryonic fibroblast (NIH/3T3), and Madin-Darby bovine kidney (MDBK) cells.

FINDINGS

HYD and DFMO suppressed the multiplication of all tested species (B. bigemina, B. bovis, B. caballi, B. divergens, and T. equi) in a dose-related manner. HFF, NIH/3T3, or MDBK cell viability was not influenced by DFMO at 1000 μM, while HYD affected the MDBK cell viability at EC50 value of 887.5±14.4 μM. The in vitro combination treatments of DFMO and HYD with CLF, DA, and ATV exhibited synergistic and additive efficacy toward all tested species. The in vivo experiment revealed that HYD and DFMO oral administration at 100 and 50 mg/kg inhibited B. microti multiplication in mice by 60.1% and 78.2%, respectively. HYD-DA and DFMO-DA combined treatments showed higher chemotherapeutic efficacy than their monotherapies.

CONCLUSION

These results indicate the prospects of HYD and DFMO as drug candidates for piroplasmosis treatment, when combined mainly with DA, ATV, and CLF. Therefore, further studies are needed to combine HYD or DFMO with either ATV or CLF and examine their impact on B. microti infection in mice.

An Expandable Mechanopharmaceutical Device (2): Drug Induced Granulomas Maximize the Cargo Sequestering Capacity of Macrophages in the Liver

PURPOSE

Drug-induced liver injuries (DILI) comprise a significant proportion of adverse drug reactions leading to hospitalizations and death. One frequent DILI is granulomatous inflammation from exposure to harmful metabolites that activate inflammatory pathways of immune cells of the liver, which may act as a barrier to isolate the irritating stimulus and limit tissue damage.

METHODS

Paralleling the accumulation of CFZ precipitates in the liver, granulomatous inflammation was studied to gain insight into its effect on liver structure and function. A structural analog that does not precipitate within macrophages was also studied using micro-analytical approaches. Depleting macrophages was used to inhibit granuloma formation and assess its effect on drug bioaccumulation and toxicity.

RESULTS

Granuloma-associated macrophages showed a distinct phenotype, differentiating them from non-granuloma macrophages. Granulomas were induced by insoluble CFZ cargo, but not by the more soluble analog, pointing to precipitation being a factor driving granulomatous inflammation. Granuloma-associated macrophages showed increased activation of lysosomal master-regulator transcription factor EB (TFEB). Inhibiting granuloma formation increased hepatic necrosis and systemic toxicity in CFZ-treated animals.

CONCLUSIONS

Granuloma-associated macrophages are a specialized cell population equipped to actively sequester and stabilize cytotoxic chemotherapeutic agents. Thus, drug-induced granulomas may function as drug sequestering "organoids" -an induced, specialized sub-compartment- to limit tissue damage.

Clinical trial for uniform multidrug therapy for leprosy patients in Brazil (U-MDT/CT-BR): adverse effects approach

BACKGROUND

The Clinical Trial for Uniform Multidrug Therapy for Leprosy Patients in Brazil (U-MDT/CT-BR), designed to evaluate the effectiveness of a six-months regimen, assessed the adverse effects caused by the drugs.

OBJECTIVE

Describe adverse effects due to MDT in U-MDT/CT-BR, comparing the uniform regimen (U-MDT) to the current WHO regimen (R-MDT).

PATIENTS AND METHODS

After operational classification, patients were randomly allocated to the study groups. U-MDT PB and U-MDT MB groups, received the U-MDT regimen, six doses of MB-MDT (rifampicin, dapsone and clofazimine). R-MDT PB and R-MDT MB groups, received the WHO regimens: six doses (rifampicin and dapsone) for PB and 12 doses (rifampicin, dapsone and clofazimine) for MB. During treatment, patients returned monthly for clinical and laboratorial evaluation. Patients with single lesion were not included in this trial.

RESULTS

Skin pigmentation (21.7%) and xerosis (16.9%) were the most frequent complaints among 753 patients. Laboratory exams showed hemoglobin concentration lower than 10g/dL in 23.3% of the patients, glutamic oxaloacetic transaminase (GOT) above 40U/L in 29.5% and glutamic pyruvic transaminase (GPT) above 40U/L in 28.5%. Twenty-four patients (3.2%) stopped dapsone intake due to adverse effects, of whom 16.6% due to severe anemia. One case of sulfone syndrome was reported.

STUDY LIMITATIONS

Loss of some monthly laboratory sample collection.

CONCLUSIONS

There was no statistical difference regarding adverse effects in the R-MDT and U-MDT groups but anemia was greater in patients from R-MDT/MB group, therefore adverse effects do not represent a constraint to recommend the six-month uniform regimen of treatment for all leprosy patients.

Safety and availability of clofazimine in the treatment of multidrug and extensively drug-resistant tuberculosis: analysis of published guidance and meta-analysis of cohort studies

OBJECTIVES

Given the spread of multidrug-resistant tuberculosis (MDR-TB), new therapies are urgently needed, including the repurposing of existing drugs. We aimed to assess key considerations for the clinical and programmatic use of clofazimine (Cfz), a riminophenazine with antimycobacterial activity currently used to treat leprosy.

DESIGN

Fixed and random effects meta-analysis of cohort studies and systematic review.

SETTING

Electronic and manual searches were combined.

INCLUSION CRITERIA

Observational studies on treatment of multidrug-resistant and extremely drug-resistant tuberculosis with Cfz or a Cfz-containing regimen, and published guidance and documents relating to cost and availability were eligible.

RESULTS

5 observational studies enrolled 861 patients, of which 602 received Cfz. The pooled proportion of adverse drug reactions requiring discontinuation of Cfz treatment was 0.1% (95% CI (0.0 to 0.6%)), and the median frequency of all adverse events was 5.1%. Cfz showed in vitro efficacy against Mycobacterium tuberculosis, and Cfz-containing regimens may have had a useful role in the treatment of patients with drug-resistant strains and who had limited alternative treatment options. However, Cfz uptake remains insufficient to meet global needs; there is only one internationally quality-assured manufacturer, which produces a limited quantity of the drug prioritised for treatment of leprosy, the only indication for which the drug is registered.

CONCLUSIONS

While the data were limited, Cfz was associated with a risk for adverse drug reactions comparable to that of first-line TB treatment, which could be reasonably managed under programmatic conditions. However, low market availability and high cost are important barriers to access to Cfz for patients with MDR-TB.

Hemolytic anemia in patients receiving daily dapsone for the treatment of leprosy

INTRODUCTION

Multidrug therapy for leprosy is currently done with dapsone, clofazimine and rifampicin. Dapsone is known to cause hemolytic anemia (HA) and this adverse event during MDT seems to be more frequent than reported. The aim of this report is to discuss and grade HA due to dapsone during MDT treatment for leprosy.

METHODS

This is a retrospective study of 194 leprosy patients from a Leprosy Control Programme Unit in Vit6ria-ES, Brazil.

RESULTS

HA was observed in 48 (24.7%) patients and occurred within the first 3 months in 51% of these. Mean hematocrit levels fell from 38.5 to 31.5 and hemoglobin from 12.8 to 10.3.

CONCLUSION

Dapsone used in the MDT regime for leprosy decreases the hematocrit and hemoglobin levels due to a low grade hemolysis, which can result in significant anemia.

Adverse effects of multi-drug therapy in leprosy, a two years' experience (2006-2008) in tertiary health care centre in the tribal region of Chhattisgarh State (Bastar, Jagdalpur)

OBJECTIVE

To assess the adverse effects of multi drug therapy (MDT) in leprosy patients.

METHODS

A prospective and descriptive study carried out in Department of Dermatology, Government Medical College, Jagdalpur. The adverse effects were recorded on the personal record of every individual patient, filled during the course of treatment.

RESULTS

176 patient's records were analysed, looking for adverse effects. Among the 176 patients, 79 had adverse effects due to one or more components of MDT, 73 had adverse effects due to dapsone, eight due to rifampicin and 16 due to clofazimine. Mean (+/- SD) duration for the development of adverse effects from the start of therapy was 1.99 (+/- 0.69) months for dapsone, 36 (+/- 0.68) months for rifampicin and 7.13 (+/- 0.79) months for clofazimine. There was a significant (P < 0.05) correlation between adverse effects and low Body Mass Index (BMI). The suspected drug was stopped and an alternative regime started in nine patients; six had dapsone stopped, two had rifampicin stopped and one had clofazimine stopped.

CONCLUSION

Adverse effects attributed to MDT are comparable to previous studies and we found that ADR due to Dapsone was very high but most of the ADR were managed by supportive treatment without replacing the suspected drug.

Longitudinal ocular survey of 202 Filipino patients with multi-bacillary (MB) leprosy treated with 2 year WHO-multiple drug therapy

The aim of this study was to describe the ocular conditions in multibacillary (MB) leprosy patients treated with 2 year WHO multiple drug therapy (MDT), consisting of dapsone, clofazimine and rifampin, a regimen expected to reduce ocular complications of leprosy. We conducted comprehensive eye examinations in 202 Filipino MB leprosy patients before, during, and after WHO 2 year MDT. Assessments were carried out for at least 5 years. Inflammatory "lepra" reactions occurred in 62% (reversal reaction, 52%; erythema nodosum leprosum, 10%); most were mild. Eye abnormalities consisted mostly of diminished corneal sensitivity before MDT (6%) and lagopthalmos (n = 7, 3.4%). Six of 7 lagopthalmos cases occurred in a subset of 132 patients with facial patches (5%). Visual acuity scores, intra-ocular pressures and pupil cycle times were unremarkable. Bacillary invasion, keratitis, episcleritis, iridocyclitis, ectropion, synechiae, glaucoma and cataract formation were not detected. Scleral clofazimine pigmentation was frequent, resolving in most within 3 years of treatment cessation. Facial patches at presentation may denote a higher risk for lagopthalmos. We propose the generally low rates of ocular problems reflected mild lepra reactions, due to anti-inflammatory properties of clofazimine, a relatively young cohort, and a readily accessible community-based clinic permitting earlier diagnosis and prompt treatment.

Use of clofazimine in dermatology

Clofazimine is the riminophenazine dye that, due to its antibacterial and anti-inflammatory properties, has been used for several diseases. This article reviews all major characteristics and uses relating to clofazimine, from its pharmacology to its indications in several skin diseases, over and above its classical and well established use in the treatment of leprosy. Due to its anti-inflammatory and antimicrobial properties, clofazimine has a wide spectrum for application in dermatology. The indications include neutrophilic, granulomatous and infectious diseases. Although it is not the first-choice medication in most of the cases, clofazimine should always be considered among the therapeutic options in refractory cases.

[Persistent type 2 lepra reaction (erythema nodosum) and clofazimine-induced lethal enteropathy]

INTRODUCTION

Clofazimine enterophathy is a serious complication of clofazimine when used at high doses for treatment of type 2 lepra or or erythema nodosum leprosum. Objective. A woman is presented who had a delayed diagnosis of leprosy, persistent type 2 lepra reaction and lethal clofazimine enteropathy.

MATERIALS AND METHODS

A 31-year-old woman presented leprosy symptoms over a 16-year period without medical diagnosis of her disease. During this period, type 2 lepra episodes occurred, but were not accurately diagnosed. These episodes became more severe during her second pregnancy. The patient and her family were interviewed, and her clinical history reviewed.

RESULTS

After twelve years of medical consults, lepromatous leprosy was diagnosed, based on perforation of her nasal septum, with a bacterial index of 5. Her husband and a 12-year-old daughter have leprosy symptoms. During multidrug therapy, she presented with repeated type 2 lepra reaction episodes for which she received daily clofazimine 400 mg doses. Two months after this treatment, severe and frequent episodes of intense abdominal pain began to occur. These persisted for more than a year and were managed with in-hospital administration of several classes of painkillers and antispasmodic medication, including morphine. She also presented with sporadic diarrhea, constipation, nausea, weight loss and mesenteric adenopathies. She died finally due to this intestinal condition. No autopsy was performed.

CONCLUSIONS

The patient's clinical presentation suggested a clofazimine-induced lethal enteropathy, a complication not previously seen in Colombia. This connection was not recognized by the medical officers that treated the patient.

A retrospective study of the effect of modified multi-drug therapy in Nepali leprosy patients following the development of adverse effects due to dapsone

INTRODUCTION

Dapsone Hypersensitivity Syndrome (DHS) occurs in approximately 2% of leprosy patients in Nepal. DHS and other adverse effects of dapsone lead to withdrawal of the drug.

METHODS

We reviewed the notes of patients who had dapsone withdrawn from their multi-drug therapy (MDT) following an adverse reaction to the drug between 1990 and 2007.

RESULTS

105 patients were identified from the database and 67 had a documented completion of a modified course of MDT. The majority were treated with rifampicin and clofazimine. All 36 individuals who were slit-skin smear positive had a satisfactory fall in their mean bacterial index. There were no cases of relapse.

CONCLUSIONS

Rifampicin and clofazimine appear to be satisfactory treatment for both paucibacillary and multibacillary patients who have to have dapsone stopped because of severe adverse effects.

Photosensitisation induced by clofazimine in a cat

A pale ginger cat was treated with clofazimine for feline leprosy. During the course of treatment, photosensitisation by clofazimine led to a dermatological disease resembling actinic dermatitis. The mycobacterial disease was eventually cured with clofazimine and the photosensitisation was managed by regulating sunlight exposure. Upon review of the literature, this appears to be the first documented case of drug-induced photosensitisation in the cat.

Adverse effects from multi-drug therapy in leprosy: a Brazilian study

INTRODUCTION

The WHO MDT for leprosy treatment was officially introduced in Brazil in 1991 and comprises three drugs: dapsone, rifampicin and clofazimine. There are few good studies on the frequency of side-effects attributable to MDT in Brazil.

METHODS

A retrospective and descriptive study carried out in a LCP in Vitória, State of Espirito Santo, Brazil. A specific and detailed protocol about side-effects was prepared and filled in from the patient records.

RESULTS

One hundred ninety four patients' records were analysed looking for side-effects attributable to MDT. Side-effects were attributed to at least one MDT component in 88 (45%) patients and 85 had side-effects due to dapsone, 24 due to rifampicin and 18 due to clofazimine. 185 episodes were identified. The suspected drug was stopped in 47 out of 88 episodes (24% patients); 46 had dapsone stopped, 5 had rifampicin stopped and no-one had clofazimine stopped.

CONCLUSION

Side-effects attributed to MDT is more frequent than previously described, resulting in interruption of treatment in many patients.

Two-year combination antibiotic therapy with clarithromycin, rifabutin, and clofazimine for Crohn's disease

BACKGROUND & AIMS

Mycobacterium avium subspecies paratuberculosis has been proposed as a cause of Crohn's disease. We report a prospective, parallel, placebo-controlled, double-blind, randomized trial of 2 years of clarithromycin, rifabutin, and clofazimine in active Crohn's disease, with a further year of follow-up.

METHODS

Two hundred thirteen patients were randomized to clarithromycin 750 mg/day, rifabutin 450 mg/day, clofazimine 50 mg/day or placebo, in addition to a 16-week tapering course of prednisolone. Those in remission (Crohn's Disease Activity Index <or=150) at week 16 continued their study medications in the maintenance phase of the trial. Primary end points were the proportion of patients experiencing at least 1 relapse at 12, 24, and 36 months.

RESULTS

At week 16, there were significantly more subjects in remission in the antibiotic arm (66%) than the placebo arm (50%; P=.02). Of 122 subjects entering the maintenance phase, 39% taking antibiotics experienced at least 1 relapse between weeks 16 and 52, compared with 56% taking placebo (P=.054). At week 104, the figures were 26% and 43%, respectively (P=.14). During the following year, 59% of the antibiotic group and 50% of the placebo group relapsed (P=.54).

CONCLUSIONS

Using combination antibiotic therapy with clarithromycin, rifabutin, and clofazimine for up to 2 years, we did not find evidence of a sustained benefit. This finding does not support a significant role for Mycobacterium avium subspecies paratuberculosis in the pathogenesis of Crohn's disease in the majority of patients. Short-term improvement was seen when this combination was added to corticosteroids, most likely because of nonspecific antibacterial effects.

Atypische Mykobakteriose der Haut durch Mycobacterium abscessus bei einer immunkompetenten Frau

Mycobacterium abscessus is the most pathogenic of the fast-growing mycobacteria, and it is resistant to most of the antimicrobial and tuberculostatic drugs available. This non-tuberculous mycobacterium is significant in medicine because it can contaminate post-traumatic wounds and be a causative agent in chronic skin and soft tissue infection after surgical procedures.A 60-year-old immunocompetent woman was suffering from chronic ulcers and abscesses on the heels and malleoli of both feet. Histological examination revealed a granulomatous inflammation with detection of acid-fast rods, albeit without fibrinoid necrosis. The repeated detection of atypical mycobacteria, which were ultimately identified as Mycobacterium abscessus, allowed the diagnosis of an atypical mycobacteriosis of the skin. This was successfully treated first with clarithromycin and rifabutin and later with a combination of ethambutol, minocycline, clofazimine and azithromycin.

Clofazimine induced enteropathy--a case highlighting the importance of drug induced disease in differential diagnosis

A patient on treatment for multibacillary leprosy for the past three years, presented with episodes of abdominal pain. Since the patient improved with conservative management, clofazimine induced enteropathy was considered as a remote possibility. A review of the mucosal biopsies showed macrophages with crystal-storing spaces consistent with clofazimine deposition in the duodenum. This case highlights the need to consider and investigate drug-induced disease as part of the differential diagnosis.

Double-blind, randomized, controlled clinical trial of clofazimine compared with chloroquine in patients with systemic lupus erythematosus

OBJECTIVE

To evaluate the efficacy of clofazimine (CFZ) compared with chloroquine diphosphate (CDP) for the treatment of cutaneous involvement in systemic lupus erythematosus (SLE).

METHODS

A prospective, randomized, controlled, double-blind clinical trial was carried out in SLE patients with active cutaneous lesions, of whom 16 were randomized to receive CFZ at 100 mg/day and 17 received CDP at 250 mg/day for 6 months. All drugs had a similar appearance to avoid identification. Both groups received broad-spectrum sunscreens twice a day and the prednisone dose was kept stable during the study. Cutaneous lesions were evaluated by 2 blinded observers at baseline and at months 1, 2, 4, and 6.

RESULTS

Thirty-three patients were randomized to a treatment group, of whom 27 completed 6 months of treatment. The groups were homogeneous and comparable in terms of demographic and clinical characteristics. Five CFZ-treated patients and 1 CDP-treated patient (P = 0.15) dropped out due to development of severe lupus flare. At the end of the study, 12 CFZ-treated patients (75%) and 14 CDP-treated patients (82.4%) had complete or near-complete remission of skin lesions; intention-to-treat analysis showed no significant difference in the response rates between groups. Side effects, mainly skin and gastrointestinal events, were frequent in both groups, but no patients had to discontinue their treatment.

CONCLUSION

These findings suggest that CFZ is equally as effective as CDP in controlling cutaneous lesions in SLE patients. However, we cannot exclude the possibility that the CFZ itself could be the cause of systemic lupus flare.

Chemotherapy of leprosy

The WHO MDT regimens have proved highly successful in preventing relapse of leprosy cases. It has indirectly lad to marked reduction in prevalence of disabilities. For PB leprosy, rifampicin 600 mg monthly and 100 mg dapsone daily for a total of 6 months therapy is required. For MB leprosy clofazimine 300 mg once monthly, supervised and 50 mg daily self administered is added. For single skin lesion the current WHO recommendation is 600 mg rifampicin + 400 mg ofloxacin + 100 mg minocycline given as a single dose for adults. Dose adjustment for children and clinical information have been discussed in a nutshell. A number of trials are going on, some are yet to be completed which do offer the prospect of perhaps simplifying therapy and improving with shorter duration.

Reactions and their management

The uneventful response to chemotherapy in leprosy is marked by clinically disturbing episodes encountered in 20-30% of patients and these phenomena are called "reactions". Generally they are classified as reversal reaction (type-1) and erythema nodosum leprosum (type-2). The cutaneous menifestations are: (1) Type-2 reactions in LL, BL types constituting erythema nodosum leprosum, erythema multiforme, erythema necroticans, subcutaneous nodules, lepromatous exacerbation. (2) Type-1 reactions in borderline and tuberculoid leprosy. The other manifestations include: Acute neuritis, lymphadenitis, arthritis, oedema of the hands and feet, ocular lesions, etc. Sequelae of reactions are: Paralytic deformities, non-paralytic deformities, extensive scarring and renal damage. A simple guideline to identify the risk-prone cases has been narrated. Prednisolone in standard dosage schedule as recommended by WHO is now being widely used in control programmes.

Intra-abdominal, crystal-storing histiocytosis due to clofazimine in a patient with lepromatous leprosy and concurrent carcinoma of the colon

We report a case with abdominal complications of clofazimine treatment which included blackish discolouration of the lymph nodes, omentum and peritoneum. A 44-year-old female with lepromatous leprosy and a history of adverse reaction to clofazimine 2 years previously, presented with rectosigmoid junction adenocarcinoma. Laparotomy revealed an inoperable tumour with pigmentation of the bowel, serosa and peritoneum. A second operation had o be performed for transverse loop colostomy and a mesenteric lymph node biopsy sent for frozen section showed typical clofazimine crystals. Despite widespread use for many years in the treatment of leprosy, this drug is not known to be carcinogenic and this case provides no evidence for an association or link between its use and the patient's cancer. Apart from its use in leprosy, clofazimine may be used in the treatment of disseminated Mycobacterium avium-intracellulare infection, Buruli ulcer due to M. ulcerans and occasionally in other mycobacterial infections. An awareness of the rare side-effect described above may help in the clinical assessment and management of such cases, including the avoidance of unnecessary laparotomy.

[Adverse effects of multidrug therapy in leprosy patients: a five-year survey at a Health Center of the Federal University of Uberlândia]

The introduction of multidrug therapy (WHO/MDT)-composed by the drugs dapsone, clofazimine and rifampicin has enabled the cure of Hansen's disease, however, the adverse effects of these drugs were not given priority by the health team. Aiming to determine MDT's adverse effects' magnitude and relate them to the non-adhesion of patients to the treatment, a study of 187 charts of patients treated with MDT from January of 1995 to May 2000, was carried out at a Health Center of the Federal University of Uberlândia. Side effects were recorded in 71 patients' charts. Among the 113 side effects found, 80 (70.7%) were related to dapsone, 7 (6.2%) were caused by rifampicin and 26 (20.5%) were attributed to clofazimine. These effects induced 28 (14.9%), patients to change the therapeutic scheme, representing 39.4% from the 71 patients with adverse effects. Throughout this study, the importance is discussed of considering MDT's adverse effects when training the health team to heighten the patient's adhesion to the treatment and thereby collaborating to eliminate Hansen's disease as a public health problem.

Biochemical and hematological side effects of clofazimine in leprosy patients

Gastrointestinal toxicity and red skin discoloration were the major side effects observed in leprosy patients undergoing long-term treatment with clofazimine (CFZ). Hematological and biochemical alterations have been cited among other side effects; however, their real magnitude and clinical significance at the doses currently employed in therapy have not been sufficiently documented. We therefore investigated the correlation between CFZ plasma concentration and biochemical (transaminases, bilirubins, alkaline phosphatase, gamma-glutamyltransferase, amylase, urea, creatinine, and potassium plasma levels) as well as hematological changes blood and reticulocyte counts, osmotic fragility, detection of Heinz bodies and methemoglobinemia (MHM), following in two regimes of treatment: CFZ as a single drug and CFZ as part of multidrug (MDT) therapy, in combination with dapsone and rifampicin. MHM and hemolytic anemia were detected in the MDT group only. Eosinophilia was found in patients of either group. Determination of hepatic, pancreatic and renal biochemical parameters showed rare, occasional changes of apparently no clinical significance. We conclude that CFZ is a generally well tolerated and safe drug when given as a daily dose of 50mg, which is currently used in leprosy patients.

Hepatic and haematological adverse reactions associated with the use of multidrug therapy in leprosy--a five year retrospective study

This study analyses retrospectively some of the risks associated with the use of WHO-multidrug therapy (MDT) in Sri Lanka. Case records of 3,333 new cases of leprosy attending the Central Leprosy Clinic in Colombo during 1991-1995, were analysed for adverse drug reactions involving the liver and blood. There were 81 reports of suspected hepatic or haematological adverse reactions associated with the use of MDT, of which 39 were classified as haemolytic anaemia, 25 as toxic hepatitis, 2 as methaemoglobinaemia and 15 as anaemia. Dapsone, was incriminated in the majority of adverse reactions (72%). Adverse drug reactions were more common in female than male subjects (55% vs 45%; P < 0.5), but there was no significant differences between the age groups. Majority of adverse reactions was seen within the first three months of initiation of MDT. This study in no way undermines the benefits of MDT but highlights the risks and suggests measures to minimize these risks.

Clofazimine enteropathy in a pediatric bone marrow transplant recipient

Clofazimine, previously used in the treatment of leprosy, is now used for treatment of Mycobacterium avium complex infection in patients with acquired immune deficiency syndrome, dermatologic disorders, and graft-versus-host disease. An 11-year-old boy developed a severe enteropathy 2 years after initiation of clofazimine treatment for graft-versus-host disease. Clofazimine enteropathy caused by crystal deposition can be life-threatening.

Clofazimine-induced crystal-storing histiocytosis producing chronic abdominal pain in a leprosy patient

Clofazimine-induced crystal-storing histiocytosis is a rare but well-recognized condition in the literature. Besides the common reddish discoloration of the skin, clofazimine produces gastrointestinal disturbances-sometimes severe abdominal pain, prompting exploratory laparotomy, because pathologic and radiologic findings can produce diagnostic difficulties if the pathologic changes caused by clofazimine are not recognized. The authors report such a case in a leprosy patient to emphasize the importance of history taking, the radiologic abnormalities of the small intestine, and the pathologic findings in small intestine and lymph node biopsies. Clofazimine crystals are red in the frozen section and exhibit bright-red birefringence. However, they are clear in routinely processed histologic sections because they dissolve in alcohol and organic solvents. They also appear as clear crystal spaces during electron microscopic study, but some osmiophilic bodies can be observed. Histiocytosis caused by clofazimine crystals produces infiltrative lesions in radiologic studies mimicking malignant lymphoma or other infiltrative disorders. Associated plasmacytosis in the histologic sections can simulate lymphoplasmacytic lymphoma or multiple myeloma with crystal-storing histiocytosis. With the knowledge of this rare condition caused by clofazimine, appropriate management to avoid an unnecessary laparotomy is possible.

A prospective randomized trial of four three-drug regimens in the treatment of disseminated Mycobacterium avium complex disease in AIDS patients: excess mortality associated with high-dose clarithromycin. Terry Beirn Community Programs for Clinical Research on AIDS

The optimal regimen for treatment of Mycobacterium avium complex (MAC) disease has not been established. Eighty-five AIDS patients with disseminated MAC disease were randomized to receive a three-drug regimen of clarithromycin, rifabutin or clofazimine, and ethambutol. Two dosages of clarithromycin, 500 or 1,000 mg twice daily (b.i.d.), were compared. The Data and Safety Monitoring Board recommended discontinuation of the clarithromycin dosage comparison and continuation of the rifabutin vs. clofazimine comparison. After a mean follow-up of 4.5 months, 10 (22%) of 45 patients receiving clarithromycin at 500 mg b.i.d. had died (70 deaths per 100 person-years) compared with 17 (43%) of 40 patients receiving clarithromycin at 1,000 mg b.i.d. (158 deaths per 100 person-years) (relative risk, 2.43; 95% confidence interval, 1.11-5.34; P = .02). After 10.4 months, 20 (49%) of 41 patients receiving rifabutin had died (81 deaths per 100 person-years) compared with 23 (52%) of 44 patients receiving clofazimine (94 deaths per 100 person-years) (relative risk, 1.20; 95% confidence interval, 0.65-2.19; P = .56). Bacteriologic outcomes were similar among treatment groups. In treating MAC disease in AIDS patients, the maximum dose of clarithromycin should be 500 mg b.i.d.

Major antileprous drug

(1) Clinical trials have shown that clofazimine monotherapy is effective. To avoid the emergence of resistance, however, the WHO reference treatment since 1982 has been the rifampicin + dapsone + clofazimine combination. (2) Epidemiological studies show that this polychemotherapy regimen is effective, but we do not yet know if treatment should be continued until skin smears become negative, or whether a 2-year course suffices. (3) Adding clofazimine to the polychemotherapy regimen partly prevents and also lessens the intensity of lepra reactions. However, in the absence of comparative trials, we do not know the part played by clofazimine in the efficacy of the WHO-recommended three-drug regimen. (4) The main adverse effects of clofazimine arise from its accumulation in the skin and eyes, where it frequently causes hyperpigmentation that resolves very slowly on treatment cessation.

A case of clofazimine enteropathy

A case of clofazimine enteropathy is described. A young male received clofazimine 200 mg daily for four years. He was admitted in a pigmented, emaciated state with abdominal pain, diarrhoea and weight loss. At laparotomy his abdominal organs were stained with dark brown-black pigment due to heavy infiltration with clofazimine crystals. Despite withdrawal of clofazimine his symptoms failed to settle. He developed oedema and hypoalbuminaemia. He died following a cerebral infarction.

Excretion of clofazimine in human milk in leprosy patients

Clofazimine is an important and effective constituent of multi drug therapy for leprosy. A study has been conducted to determine the distribution of clofazimine in maternal milk so that the safety of breast-feeding during maternal ingestion of the drug can be ascertained. Eight female leprosy patients (LL/BL) on clofazimine, 50 mg daily or 100 mg on alternate days for 1-18 months, (mean 5.0 +/- 1.81 months; median 3.25 months) and in the early lactating phase were studied. Blood samples and milk specimens were collected 4-6 hr after the last daily dose. Clofazimine was assayed in the milk and plasma samples by HPTLC. Mean plasma and milk clofazimine levels were 0.9 +/- 0.03 micrograms/ml and 1.33 +/- 0.09 micrograms/ml respectively. The ratio of milk to plasma drug concentration ranged from 1.0 to 1.7 with a mean of 1.48 +/- 0.08. The amount of drug ingested by the infants was 0.199 +/- 0.013 mg/kg/day which represented 22.1 +/- 1.9% of the maternal dose.