8.5 Tuberculosis drug formulations

Only quality-assured drugs should be used. Several internationally recognized mechanisms ensure the quality of TB drugs a Citation a. Quality assurance:
• WHO Prequalification Scheme: http://apps.who.int/prequal/
• Stringent Regulatory Authorities (SRA): https://stoptb.org/assets/documents/gdf/drugsupply/list_of_countries_sra.pdf ^, b Citation b. Supply:
Global Drug Facility (GDF): https://www.stoptb.org/facilitate-access-to-tb-drugs-diagnostics/global-drug-facility-gdf .

8.5.1 Fixed-dose combinations

FDC formulations combine several TB drugs (2, 3 or 4) in the same tablet. FDCs are only available for first-line TB drugs.

FDCs improve adherence (decreased pill burden, decreased risk of omission of one or more drugs).

Table 8.6 – Quality-assured FDC formulations

Note: when needed in children, ethambutol is given as a single formulation, in addition to the paediatric FDCs.

8.5.2 Individual drugs

Quality-assured single drug formulations are available for all first-line TB drugs. It may be necessary to use them when FDCs cannot be used due to adverse effects or drug interactions.

There are no quality-assured FDCs for second-line TB drugs. The treatment of DR-TB is based on a combination of individual drugs.

8.5.3 Paediatric formulations

Paediatric formulations should be used whenever possible.

For oral drugs with doses expressed in ml (oral solutions and suspensions), always use the measuring device included in the packaging by the manufacturer. If the measuring device is not provided with the drug, use an oral syringe, a measuring spoon or a medicine cup with graduations.

However, paediatric formulations are not available for all TB drugs. When the only option is to manipulate the adult formulations:

• Preferably use scored tablets.
• Ensure that tablets/capsules can be split, crushed or opened (e.g. active ingredients may be protected from gastric acidity by an enteric coating).
• If tablets must be crushed (or capsules opened), a fraction of the powder corresponding to the required dose is mixed with food or liquids. Such manipulations should be done immediately before administering the drug. Any remaining powder should be discarded.
• The preparation of extemporaneous formulations using adult formulations is an alternative, however, this can only be considered if there are qualified personnel to ensure preparation in compliance with the appropriate compounding procedures.