Herbal Medicinal Products
Applications for the registration of a traditional herbal medicinal product should be submitted in accordance with the Austrian Medicines Act (Arzneimittelgesetz, AMG) as amended. The documents to be submitted as part of the application for registration are specified in Article 12a AMG, and they should be submitted in CTD format, preferably electronically.
The applicant has to demonstrate the following: The indications are exclusively appropriate to traditional herbal medicinal products. The medicinal product is, by virtue of its composition and purpose, designed for use without prescription. The medicinal product is exclusively designed for administration in accordance with a specified strength and posology. A corresponding product has been in medicinal use throughout a period of at least 30 years, including at least 15 years within the European Economic Area. The data on the traditional use, including safety and plausibility of efficacy, are sufficient. The traditional use can be demonstrated either by bibliographical data or by means of an expert report. No additional demonstration of the traditional use is required when a reference is made to a Community Monograph according to Article 16(h)3 of Directive 2001/83.
For combinations with vitamins or minerals and for medicinal product containing more than one active ingredient, data on the combination should be provided. In case traditional use has been demonstrated for the combination, but not for the single active substances, data on the single active substances should be provided.
Evidence of a person responsible for pharmacovigilance; description of the pharmacovigilance system and (if appropriate) the risk management system.
Details are given in Articles 12 and 12a AMG.
A corresponding herbal medicinal product has the same active ingredient, the same or similar indications, an equivalent strength and posology, and the same or a similar route of administration, as the herbal medicinal product which is submitted for registration.
The phrase ‘same active ingredient’ is somewhat difficult to interpret, especially with respect to extracts from herbal drugs. However, what is clear is that ‘same active ingredient’ means the same plant, plant part, and extraction solvent; moreover, a similar concentration of the extraction solvent (especially with water-alcohol mixtures) and a similar drug-extract ratio are required. Overall, therefore, the traditional herbal medicinal product must be closely related to published data or to other medicinal products.
If the active substance deviates with regard to the mentioned parameters a comprehensive comparison using different analytical methods would be necessary to demonstrate the chemical equivalence to the corresponding product.
Evidence of traditional use can be demonstrated through any form of scientific documentation. Also, it is important to document that the medicinal use of the product has not been just sporadic, but that the product has been used continuously over longer periods within the requested 30 years.
If the product submitted for registration is in line with a community monograph of the HMPC the contents of modules 2.4 and 2.5 (evidence for traditional use) can be replaced by a cross reference to the monograph and the respective assessment report.
If reference is made to a corresponding authorized or registered medicinal product the evidence for the long-standing use should be supported by marketing authorization data as well as evidence for the authorized indication and posology.
The ‚Guideline on the assessment of clinical safety and efficacy in the preparation of community herbal monographs …‘ (Doc. Ref. EMEA/HMPC/104613/2005) should be applied in case that the evidence on the traditional use is justified by standard references for phytotherapy.
The quality aspect of a medicinal product is independent from its traditional use. Therefore, no exemptions can be made with respect to the physicochemical, biological, and microbiological data to be submitted.
Traditional herbal medicinal products may contain herbal drugs which are not the subject of a pharmacopoeia monograph and for which only limited analytical procedures have been published. Therefore, the quality of traditional herbal medicinal products must be determined on a case-by-case basis, taking into consideration its composition and the analytical procedures available to document its quality.
The following guidelines should be considered:
‚Guideline on quality of herbal medicinal products1/traditional herbal medicinal products‘ (Doc. Ref. EMA/CPMP/QWP/2819/00 Rev. 2)
‘Guideline on specifications: test procedures and acceptance criteria for herbal substances, herbal preparations and herbal medicinal products/ traditional herbal medicinal products’ (Doc. Ref. EMA/CPMP/QWP/2820/00 Rev. 2)
‘Guideline on quality of combination herbal medicinal products / traditional herbal medicinal products’ (Doc. Ref. EMEA/HMPC/CHMP/CVMP/214869/2006)
Yes, stability tests are necessary both for the active substance(s) and for the finished product. The data have to be submitted as part of the registration dossier. When adequate instructions for storage are foreseen, stress tests at higher temperatures may be waived.
The selection of adequate analytical markers may be difficult, especially for preparations containing several herbal drugs. The applicant should try to document that the extracts in their totality are sufficiently stable.
Herbal drugs contained in a monograph must, throughout their entire shelf-life, fulfil the requirements of the pharmacopoeia.
For herbal drugs not contained in a monograph, the content of essential oil at the end of the shelf-life must be within the standard limits given in the scientific literature.
If the traditional herbal medicinal product submitted for registration is in line with a community monograph of the HMPC or it consists of herbal substances, preparations or combinations thereof contained in the Community list MRP/DCP shall apply.
If the THMP deviates from the HMPC monograph or the list entry MRP/DCP is possible on a voluntary basis. Discussion with Member States intended to be included in any procedure is recommended before submission of an application. See also the Q&A on traditional herbal medicinal products of the CMDh.
Herbal preparations are obtained by subjecting herbal substances to treatments such as extraction, distillation, expression, fractionation, purification, concentration or fermentation. These include comminuted or powdered herbal substances, tinctures, extracts, essential oils, expressed juices and processed exudates.
The degree of purification, fractionation or concentration is neither defined nor limited in the legislation. Therefore also purified substances of herbal origin (like D-Camphor) are acceptable as active ingredient in traditional herbal medicinal products. See also the regulatory Q&As of the HMPC.
Evidence of at least 30 years of medicinal use has to be provided for the herbal active substance or the combination of the herbal active substances. For additional vitamins and minerals data have to be submitted for the substantiation of the ancillary action in the proposed indication and posology.
The term "well-established use" corresponds with the bibliographic application according to §10a AMG.
For herbal medicinal products in the dossier particular importance should be paid to the comparability of the product submitted for marketing authorisation and the reference products which were used in the published non-clinical and clinical investigations. A formal equivalence regarding the plant source, the plant part used, the extraction solvent and the drug-extract-ratio is essential. Analytical data demonstrating the similarity between the product submitted and the reference product may be asked for.
The non-clinical and clinical data have to comply with the current scientific standards.
If the product submitted for marketing authorization is in line with a community monograph for well-established use of the HMPC the contents of modules 2.4 and 2.5, 4 and 5 can be replaced by a cross reference to the monograph and the respective assessment report. Relevant scientific data which has been published since the publication date of the HMPC monograph should be presented in the dossier and discussed taking into account the HMPC assessment report.
Because toxicologically relevant concentrations of pyrrolizidine alkaloids may result from contamination with very few plants (e.g. species of the genus Senecio, ragwort), appropriate control cannot be assured with measurements based on “Good Agricultural and Collection Practice” only. Therefore analyses of certain herbal substances and herbal preparations are required.
Based on the experience gained so far it can be assumed that
- Hyperici herba,
- Passiflorae herba,
- Matricariae flos,
- Alchemillae herba,
- Liquiritiae radix,
- Melissae folium,
- Menthae piperitae folium,
- Salviae folium,
- Taraxaci herba cum radice,
- Thymi herba,
- Equiseti herba,
- Urticae radix,
- Urticae herba, Urticae folium
- and preparations thereof
may contain PA in considerable amounts. Therefore marketing authorization holders or registration holders of herbal medicinal products, traditional herbal medicinal products, as well as of pharmacy-proprietary medicinal products and of homoeopathic medicinal products with active substances of the above mentioned herbal substances or herbal preparations thereof have to collect data on the content of toxic pyrrolizidine alkaloids. Essential oils are currently not in the scope of this obligation.
The BASG reserves the right to modify the list of plants which have to be analysed depending on the results obtained from now.
Irrespective of the above mentioned list all authorization holders / registration holders are responsible for a product specific risk evaluation.
Therefore, if applicable, testing of herbal preparations of other plants may be required.
Irrespective of the above mentioned list all herbal preparations (herbal drugs, herbal preparations) of plants, which biosynthesise PA (e.g., species of the genera Cynoglossum, Petasites, Senecio, Jacobaea symphytum, Eupatorium, Tussilago), have to be tested on the PA content.
The limits have to comply with the recommendations of the Committee on Herbal Medicinal Products (HMPC) of the European Medicines Agency (EMA) (EMA/HMPC/893108/2011 Rev. 1). The limit of 1.0 µg PA with respect to the maximum daily dose of the finished product must not be exceeded for adults. For children and adolescents the limit has to be calculated on the basis of a maximum daily exposure of 0.0237 µg/kg BW. The body weight should be taken from recognised sources, where such growth tables have to be used where an adult is given with 50 kg. In the case that the drug product is foreseen for different age groups with different posologies, the lowest limit has to be set in the release specification.
A reduced testing scheme is in principle acceptable. The testing frequency has to be established related to the actual contamination and the limit set in the release specification. Based on the testing scheme with a maximum daily exposure of 1.0 µg for adults the following testing scheme is applicable considering the posology for children and adolescents and available batch data:
- No or very low contamination 90% of the investigated samples of a herbal preparation results in a contamination of ≤ 10.0% of the limit set in the release specification of the drug product. No sample leads to more than 35.0% of this limit. Skip testing is acceptable. The testing scheme must be justified on the basis of batch data and has to be authorised in a procedure (marketing authorisation, registration, variation).
- Low contamination 90% of the investigated samples of a herbal preparation results in a contamination ≤ 35.0% of the limit set in the release specification of the drug product. No sample leads to more than the limit set in the release specification. Skip testing with shorter intervals is acceptable. For dossier requirements see category 1.
- Relevant contamination. If categories 1 and 2 are not applicable a routine testing on PA content in the release specification has to be implemented.
In the case of a change of the supplier of the herbal substance the reduced testing scheme has to be re-evaluated within a variation procedure.
The risk of a contamination with PA has to be fully addressed in the dossier.
The actual testing should be performed on the extract or the drug product. Only in justified cases testing is acceptable at the stage of the herbal starting material (e.g. herbal teas). In this case special care should be exercised on the sampling plan (risk of spot contamination, chapter 2.8.20 of Ph. Eur. is applicable). The results obtained from herbal preparations can be extrapolated to the finished product. In the case of combination medicinal products the impact of all herbal ingredients has to be considered.
The applicant is advised to use the method according to Ph. Eur. chapter 2.8.26. (Contaminant pyrrolizidine alkaloids) considering the requirements for validation and verification. The data from validation / verification as well as data of all reference standards have to be contained in the dossier.
If the method is used for analysis of herbal preparations of plants which biosynthesise PA (e.g. species of the genera Cynoglossum, Petasites, Senecio, Jacobaea, Symphytum, Eupatorium, Tussilago) the suitability has to be demonstrated on a product-specific basis.
Herbal medicinal products are not in the scope of chapter 5.20. However, also herbal medicinal products must comply with general principles regarding the contamination with elemental impurities. The risk assessment should follow the Guideline on the formalised risk assessment for ascertaining the appropriate good manufacturing practice for excipients of medicinal products for human use (2015/C 95/02).