Abstract
Aim and Objectives: To examine the concordance of the Libyan Pharmaceutical List of Essential Medicines (LPLEM) with the World Health Organization Model List of Essential Medicines 2009 (WMLEM 2009).
Methods: The concordance between generic medicines listed in the WMLEM 2009 (standard reference list) and the LPLEM 2006 (comparator list) was evaluated.
Results: The total number of Basic Essential Medicines (BEMs) listed on the WMLEM 2009 was 347. The total number of generic medicines listed on the LPLEM was 584. Although the LPLEM has more listed medicines, only 270 (77.6%) of BEMs from the WMLEM were listed as available. However, 25 of the 77 missing medicines were deemed to have appropriate alternatives. A total of 52 medicines from the WMLEM 2009 were therefore missing from the LPLEM. Discrepancies compared to the WMLEM 2009 were identified in 15 out of 29 therapeutic sections. The highest discrepancy rate from the WMLEM 2009 was in the anti-infective section (35 missing medicines). Missing BEMs were noted in many subclassifications of the anti-infective medicines section, but omissions were particularly prevalent in the antibacterial medicines subsection (11 missing medicines). Antituberculosis medications had the highest discrepancy rate for antibacterial BEMs with one-third of the single medicines recommended by the WHO in the WMLEM 2009 not listed on the LPLEM. Of the 314 additional medicines on the LPLEM, 18 were deemed to be irrational non-essential medicines.
Conclusion: The LPLEM does not include several essential medicines recommended by the WHO in the WMLEM 2009. These discrepancies may have serious public health implications for management of some infectious diseases, particularly, tuberculosis and HIV.
Introduction
A National Essential Medicines List (NEML) is central to the sound management and supply of essential medicines to any society Citation1. Appropriate selection of essential medicines for a NEML has been considered by the World Health Organization (WHO) as the most cost-effective health intervention after childhood immunization Citation2. The appropriate selection of medicines can assist with the management and supply of medicines and, as a result, curb the financial burden caused by pharmaceuticals on national health budgets Citation3. According to the WHO, a NEML should encompass a limited group of medicines that are of proven safety, efficacy, and cost effectiveness Citation4. This limited group of medicines has been named by the WHO as essential medicines Citation2. Under ideal circumstances essential medicines are defined within the national context and according to the prevalent diseases and conditions in a given society Citation5. Since this capacity is limited in many developing countries Citation1, the WHO has identified a subset of medicines to treat the world's most common diseases and conditions. This subset of medicines is listed in the WHO model list of essential medicines (WMLEM) and has been regularly updated since 1977. Essential medicines listed in the WMLEM represent the minimum number of medicines that should be available within any fully functioning health care system and need to be the foundation of any NEML Citation2Citation6.
Libya is an upper middle-income North African nation that strives for high standard health care services Citation7. Historically, the Libyan national standard list of medicines was used by the public pharmaceutical sector of the Libyan health care system Citation8Citation9 for the procurement and government subsidy of medicines for Libyan society. Medicines are also supplied by the private pharmaceutical market; however, access to medicines from the private market is often prohibitively expensive.
The Libyan national standard list of medicines, which was commonly known as the Libyan Pharmaceutical List (LPL), was previously the list of all registered medicines used in the Libyan health care system Citation8. Since the LPL was too extensive to use for the general procurement of medicines, government subsidy, and also encompassed several unsafe and superseded medicines, it had been implicated by local researchers Citation8Citation9 and the WHO Citation7 as a contributor to the problem of medicines management and supply in Libya. As a result, the LPL was cancelled by the National Committee of Drugs Citation7 and replaced by a new Libyan national standard list of medicines – the Libyan Pharmaceutical List of Essential Medicines (LPLEM) in 2006. According to the Directorate of Pharmacy and Medical Equipment in the Libyan Ministry of Health, the LPLEM 2006 encompassed only essential medicines (rather than all registered medicines in the health system) as advocated by the WHO. The LPLEM 2006 continues to be the current Libyan national standard list for procurement and government subsidy of medicines.
The continuing problem of medicines management and supply to Libyan society has been acknowledged by the Libyan Government in several recent press releases Citation10. Therefore, the aim of this study was to examine the LPLEM 2006 in relation to compliance with the WHO recommendations for medicines selection in order to identify or exclude the LPLEM 2006 as a potential contributor to the suboptimal management and supply of essential medicines in Libya.
Methods
The concordance between the WMLEM 2009 and the LPLEM 2006 was compared based on the method utilized by Jafarov Citation11. All medicines listed in the WMLEM 2009 were considered as Basic Essential Medicines (BEMs) since they represent the minimum formulary of medicines that should be available for a country's health care system. Both the core medicines list and complementary medicines list were reviewed. The core medicines list details medicines that meet the minimum needs for a basic health care system, whereas the complementary medicines list catalogues drugs used for priority diseases for which specialized diagnostic or monitoring facilities, specialist medical care, and/or specialist training are needed.
Generic medicine concordance
The WMLEM 2009 was used as the standard reference list for comparison (including the therapeutic sections) and the LPLEM 2006 was the subject list. Since both lists were not fully super imposable, a spreadsheet was constructed to allow head-to-head comparison. Information in relation to both lists was inserted in a comparative matrix that allowed for evaluation of available BEMs (medicines from the WMLEM 2009 that were available on the LPLEM based on generic name), missing BEMs (medicines from the WMLEM 2009 that were not available on the LPLEM based on generic name), additional available medicines (medicines on the LPLEM but not listed on the WMLEM 2009), or alternative available medicines. A medicine was deemed by the reviewers to be an alternative available medicine to a listed BEM from the WMLEM 2009 based on either being in the same pharmacological class (e.g. tetracaine and oxybuprocaine) or if having an ‘equivalent’ therapeutic action (e.g. DL-methionine and N-acetylcysteine).
If a medicine was listed in more than one therapeutic section (e.g. morphine was listed in both the analgesics and anesthetics sections) or was available in an alternative therapeutic section, the medicine was recorded as available.
Formulation and dosage reconciliation for available Basic Essential Medicines (BEMs)
For available BEMs, the number of product formulations and strengths were identified and reconciled as follows:
Available BEMs that were presented in the LPLEM in total concordance with those recommended by the WHO in the WMLEM 2009.
Available BEMs that were presented in the LPLEM with less or more dosage forms and/or product strengths than those recommended by the WHO in the WMLEM 2009.
Results
Generic medicine concordance
The total number of medicines listed in the WMLEM 2009 was 347. The total number of medicines listed on the LPLEM was 584. Based on generic identification of counterparts from both lists, the LPLEM complied fully with the recommendations of the WHO with regards to essential medicines in 14 of the 29 standard therapeutic sections. Detailed information in relation to number of available BEMs per therapeutic section is illustrated in .
Table 1. Missing BEMs per therapeutic section
Available Basic Essential Medicines (BEMs)
From the list of 347 BEMs on the WMLEM 2009, only 270 (78%) BEMs were listed as available on the LPLEM.
Missing Basic Essential Medicines (BEMs) for which alternatives were available
Based on direct generic medicine concordance with the WMLEM 2009, 77 (22%) of medicines recommended by the WHO in the WMLEM 2009 were therefore missing from the LPLEM (missing BEMs). However, for 25 (32%) of these missing BEMs therapeutic, alternatives were available via another known channel of supply within the Libyan health system, were culturally unacceptable, or irrelevant to the Libyan disease demographic. In more detail:
Eight (10%) of the missing BEMs have therapeutic alternatives on the LPLEM. Of these, five had alternatives that are chemically different but are from the same pharmacological class (e.g. tetracaine and oxybuprocaine), while three BEMs had an alternative drug that could be considered therapeutically similar (e.g. DL-methionine and N-acetyl cysteine).
Some medicines from the dermatological section (n=7), endocrine section (n=1), vitamins and minerals section (n=1), and the ear nose and throat conditions in the children section (n=1) were not listed on the LPLEM. However, these products are available on request as extemporaneously manufactured products (e.g. potassium permanganate 1 in 10,000 solution, benzoic acid 3%/Salicylic acid 6% ointment, etc.) and have therefore been omitted from the missing BEMs group (see ).
Some endocrine contraceptives products (n=3) and oxytocics (n=1) are not included on the LPLEM for cultural or legal reasons (see ).
Some therapeutic substances (oxygen gas and ethanol) are supplied by other Libyan government bodies of medical supply Citation9.
The Japanese encephalitis vaccine (n=1) is irrelevant to the Libyan national disease profile.
Table 2. Missing BEMs for which alternatives were identified
Table 3. Distribution of missing BEMs among various standard therapeutic sections
Missing Basic Essential Medicines (BEMs)
Missing BEMs (see ) were distributed over 15 out of 29 standard therapeutic sections with the highest number of missing medicines in the anti-infective section (n=35). Missing BEMs from the anti-infective medicines section (see ) were distributed over various subsections with the highest recorded discrepancy in the antibacterial medicines subsection (n=11). One-third of antituberculosis medications recommended by the WHO in the WMLEM 2009 were not listed on the LPLEM. In addition, all fixed dose combinations recommended by the WMLEM were not listed on the LPLEM.
Table 4. Missing BEMs from the anti-infective medicines section
Six out of seven missing BEMs from the antiviral subsection were antiretroviral medicines. Of these, four were fixed dose combinations and two were single medicines. Nine medicines were also missing from the antiprotozoal subsection.
Additional medicines available on the Libyan Pharmaceutical List of Essential Medicines (LPLEM)
After review there were 314 medicines on the LPLEM deemed to be additional. Of these, 274 were classified under the same therapeutic sections adopted by the WHO in the WMLEM 2009. However, of these 274 medicines, 18 were deemed by the reviewers to be non-essential medicines (see ). Forty of the additional medicines listed on the LPLEM fall outside the perimeters of the classification system for BEMs used by the WHO. These products include dietary supplements, pharmaceutical chemicals, and rodenticides.
Table 5. Non-essential medicines identified in the LPLEM
Formulation and dosage reconciliation for available Basic Essential Medicines (BEMs)
Of 270 available BEMs, 172 were presented in the LPLEM in total concordance with those recommended by the WHO in the WMLEM 2009, 67 were presented in the LPLEM with less dosage forms and/or product strengths than those recommended by the WHO in the WMLEM 2009, and 31 were presented in the LPLEM with more dosage forms and/or product strengths than those recommended by the WHO in the WMLEM 2009.
Discussion
According to the WHO guidelines, a NEML is central to medicine's management and supply for any society Citation1. However, in order for a NEML to contribute positively to the national medicines situation, medicines on the list must first be selected appropriately. Full discussion of the ideal process of medicines selection is beyond the scope of this paper. However, the WHO states that appropriate selection of medicines for a NEML is a process that requires several tenets to be carefully considered Citation2. Firstly, medicines need to be selected from a pool of safe and effective medicines underpinned by a sound medicine registration system Citation1. Secondly, medicines on the NEML should reflect the treatment requirements of nationally prevalent diseases that have been identified and examined by a robust epidemiological reporting process. In order for national decision makers to act accordingly, national health indicators that reflect morbidity and mortality trends must be available Citation2. In addition, other supportive measures need to be implemented. A national system to identify microbial resistance patterns, as well as educational and government processes to provide personnel well trained in current therapeutics, morbidity trends, critical appraisal, and pharmacoeconomics Citation12 need to implemented. As stated by local researchers, the capacity to perform such tasks in Libya needs to be improved Citation8Citation9.
Since epidemiological data regarding the Libyan national disease profile is not readily available Citation7Citation13, the LPLEM was evaluated in comparison to the WMLEM as a potential contributor to medicine availability problems in Libya. The WHO recommends that all medicines listed on the WMLEM be available in any fully functioning health system Citation2 unless the medicine is legally unacceptable, culturally improper, or irrelevant to the national disease profile Citation14. The analysis demonstrated that the LPLEM fully complied with medicines recommended by the WHO in the WMLEM 2009 in 14 out of 29 therapeutic sections. However, many BEMs were not listed as available in other therapeutic sections. Even after considering possible therapeutic alternatives, there were 52 missing BEMs from the LPLEM. There was one BEM not listed in the gastrointestinal, muscle relaxant, vitamins and minerals, specific medicines for neonatal care, and medicines for ear nose and throat conditions in children therapeutic sections; two BEMs not listed in the endocrine, immunological, and psychotropic therapeutic sections; and three BEMs not listed in the antidotes and dermatological therapeutic sections.
The area of greatest concern was the anti-infective section, where 35 medicines from the WMLEM were not listed on the LPLEM. The WHO states that several communicable diseases such as tuberculosis, HIV/AIDS, malaria, and leishmaniasis still impose a threat to Libyan society Citation7Citation13
It is important to reinforce that risks imposed by suboptimal anti-infective medicine selection have the capacity to extend well beyond an individual patient Citation15. The LPLEM was suboptimal in relation to inclusion of essential anti-infective medicines from the WMLEM 2009 for all subsections of anti-infective medicines. The highest recorded discrepancy from the anti-infective section was with antituberculosis medicines (see ). Antituberculosis medicines recommended in the WMLEM 2009 are either single medicines or fixed dose combinations. Four single medicines, including the first-line antituberculosis medicine, rifabutin, were not listed on the LPLEM. Five first-line antituberculosis fixed dose combinations were also not listed on the LPLEM (see ). Although all individual medicines included in these fixed dose combinations were listed on the LPLEM, this does not necessarily provide the best mechanism to ensure treatment effectiveness, patient compliance, and does not eliminate the need for fixed dose combinations Citation16Citation17. Fixed dose combinations of antituberculosis medicines offer several advantages since they reduce the number of capsules or tablets that must be ingested daily, decrease the likelihood of resistance, improve clinical outcomes, enhance patient compliance, simplify treatment regimens, and facilitate logistics Citation16Citation18Citation19. Fixed dose combinations can only be excluded in settings where the WHO recommendations in relation to tuberculosis treatment (e.g. the Directly Observed Short Course, DOTS, strategy) are strictly implemented Citation17Citation18. Nevertheless, even in such settings, fixed dose combinations enhance patient compliance by decreasing ‘pill burden’ Citation18. The importance of providing the best available pharmaceutical products, including fixed dose combinations to treat tuberculosis, is reinforced by evidence of a substantial increase in the number of reported tuberculosis cases over the last 15 years in Libya Citation20. In addition, although information from the WHO Libyan country profile Citation13 indicates the existence of multidrug resistant tuberculosis, three out of seven treatments recommended by the WHO for the treatment of multidrug resistant tuberculosis were not listed on the LPLEM. Also of concern is the continued listing of thiocetazone (as an additional medicine antituberculosis in the medicines section on the LPLEM), a drug whose use is diminishing due to safety concerns and questionable efficacy Citation21. Thiocetazone has weak activity against Mycobacterium tuberculosis and offers no advantage over ethambutol Citation22.
Results from the comparative analysis demonstrated another major discrepancy in the antiretroviral medicines section. HIV/AIDS is not currently a major cause of morbidity and mortality in Libya, however its incidence is increasing among injecting drug users Citation7. Two single as well as four fixed dose combinations were missing from the LPLEM (see ). As with tuberculosis treatment, fixed dose combinations reduce pill burden, minimize (prescribing, dispensing, and use) errors, and improve logistics Citation23. Triple antiretroviral combinations employing fixed dose combinations are the most convenient and affordable options for treatment Citation16.
The analysis of the antiprotozoal subsection demonstrated that one of three BEMs (paronomycin) used for the treatment of leishmania infections (see ) is missing from the LPLEM. Leishmaniasis is endemic in some areas of the Libyan nation Citation24 and is an increasing problem not only in Libya but also in the whole African continent Citation10. Three BEMs used to treat malaria are also not listed on the LPLEM. Although malaria is not a major disease problem in Libya Citation7 since isolated cases still require treatment, all BEMs to treat malaria should be available.
Missing BEMs from the LPLEM that have implications for children and neonatal care (n=4), include caffeine citrate and rotavirus vaccine. Caffeine citrate is preferred to aminophylline for the treatment neonatal apnea of prematurity due to a better adverse effect profile and a , a longer elimination half-life Citation25, and hence should also be listed on the LPLEM. Rotavirus vaccine is a major cause of childhood diarrhea in Libya Citation26 and is highly recommended by the WHO to be included in national immunization programs. Clinical trials of rotavirus vaccine in high-mortality, low-socioeconomic settings of South Africa and Malawi have found that the vaccine significantly reduced severe diarrhea episodes due to rotavirus Citation27.
Another area of concern is antidote medicines. Although uncommon, thallium and cyanide poisonings are potentially life threatening Citation28Citation29. Prussian blue, the antidote of choice for treatment of thallium toxicity Citation30 as well as sodium nitrite and sodium thiosulfate to treat cyanide poisoning Citation31, need to be listed on the LPLEM.
Of 21 dermatological medicines, 3 were missing from the LPLEM (see ). The inclusion of malathion on the LPLEM (within the group of additional medicines) does not eliminate the need for permethrin. No significant difference exists in regarding their efficacy against head lice Citation32 and permethrin requires less application time and is a safer alternative in most cases.
The 2002 definition of essential medicines Citation2 clearly states that there is no upper limit for inclusion of medicines on a NEML; however, the definition set out by the WHO clearly indicates that the optimization of essential medicines be the principal priority Citation2. The LPLEM included a high number of additional medicines (n=274) that exceeded the number of essential medicines on the list (n=270). This group of additional medicines on the LPLEM included some medicines that were deemed to be non-essential. Some of the non-essential medicines could be considered obsolete since newer alternatives from the same class exist on the LPLEM. Specific examples include nalidixic acid and tetracycline. Nalidixic acid has been superseded by other quinolones Citation33 while doxycycline has largely replaced tetracycline worldwide Citation34. The inclusion of the fixed dose combination of chlordiazepoxide and clidinium bromide cannot be justified in 2010 as a necessary product for a NEML. The LPLEM also included additional medicines with poor safety profiles such as maprotiline, a third-line tetracyclic antidepressant with a higher epileptogenic potential than many alternative antidepressants available on the LPLEM Citation35.
This study of the generic concordance of medicines between the LPLEM and the WMLEM 2009 did not reconcile product (dosage forms and dosage strengths) discrepancies among both lists. For example, pyrazinamide was deemed as an available BEM on the LPLEM; however, pyrazinamide was listed only as a 500 mg tablet, whereas the WMLEM 2009 recommends multiple formulations and strengths (30 mg/ml oral liquid, 400 mg tablet, 150 mg dispersible tablets, and 150 mg scored tablets). The review of appropriate dosage form and strength selection is also an important aspect of rational selection of medicines for NEMLs that requires further research.
The discrepancies between the LPLEM 2006 and the WMLEM 2009 highlight the need for continual review of the LPLEM. Future discrepancies can be prevented if the list is reviewed continually or at least annually.
Conclusion
This analysis of the LPLEM in reference to the WMLEM 2009 has several implications for medicines management and supply in Libya. In order to cater for the essential medicines needs of the Libyan health system, all aspects of appropriate medicine selections advocated by the WHO need to be considered. The establishment of a standardized evidence-based process of medicines selection that complies with the WHO recommendations is the one and only avenue that can systematically build a robust NEML that fulfils the societal needs of medicines. The anti-infective section in the LPLEM has demonstrated the highest discrepancy from the WHO recommendations and requires urgent review. In addition, the LPLEM still includes several medicines with safety concerns or with minimal evidence of clinical efficacy. The entire process of development and updating the LPLEM requires further consideration and improvement.
Conflict of interest and funding
The authors have not received any funding or benefits from industry or elsewhere to conduct this study.
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