Supply · Shelf life

How much remaining shelf life should an export shipment have?

No single figure applies. WHO Technical Report Series No. 1025, Annex 8, says remaining shelf life should be set for each importer by risk assessment and agreed in writing. Its example table suggests, for a total shelf life over 36 and up to 48 months, 30 months at dispatch, 24 at port of entry and 12 at the end user.

Why does remaining shelf life matter to an importer?

Because a product that arrives close to expiry may not be used before it expires. A shipment to a distant market spends time in transit, at customs and in local distribution before it reaches a patient, and every month of that comes out of the shelf life the manufacturer assigned. The World Health Organization addressed this directly in WHO Technical Report Series No. 1025, Annex 8, Points to consider for setting the remaining shelf-life of medical products upon delivery, published in the Fifty-fourth report of the WHO Expert Committee on Specifications for Pharmaceutical Preparations (2020).¹

What exactly is remaining shelf life?

It is the time left between delivery and expiry. WHO Technical Report Series No. 1025, Annex 8, section 3, defines remaining shelf life as the period remaining, from the date upon delivery, to the expiry date, retest date, install by date or other use before date established by the manufacturer.¹

Two other definitions in the same glossary are worth knowing. Shelf life is the period, from the date of manufacture, that a product is expected to remain within its approved specification while handled and stored under defined conditions. And "upon delivery" is not fixed: WHO says it is the date the product is delivered as specified, for example at the port, at the point in country after customs clearance, or at the end user, as defined in the agreement between the parties.¹ A remaining shelf life figure is therefore meaningless until both sides agree where delivery happens.

Does WHO set a fixed minimum?

No. Section 5.1 of Annex 8 says decisions on remaining shelf life should be defined realistically, contextualised and adapted to each importer, following a thorough risk assessment.¹ It lists the factors to weigh, including but not limited to:

• the category and type of product;
• inventory level;
• manufacturing and transit lead time;
• local release lead time;
• storage condition;
• the delivery chain; and
• resources in the recipient country or region.

The same section says there should be agreements between suppliers, purchasers and recipients covering the responsibilities of each party, including remaining shelf life or expiry date.¹ For what else belongs in such an agreement, see distribution agreement essentials.

What does WHO's example table say?

Appendix 1 of Annex 8 gives an example of minimum remaining shelf life at three points in the chain, based on the outcome of risk assessment. WHO describes it in section 5.3 as an illustrative example, not a universal rule.¹ The figures, from Table A8.1, are:

Notice that the table is written in absolute months for each shelf life band, not as a percentage of total shelf life. A supplier who quotes a percentage rule and attributes it to WHO is not quoting this document. Notice too that products with a total shelf life of 12 months or less are left to special arrangements rather than given a number.

The note under the table says total shelf life comes from stability studies, and where relevant sterility studies, under specified conditions, and that the storage and transport conditions stipulated by the manufacturer should be followed.¹

Can a buyer extend shelf life by retesting?

Generally, no. Section 5.3 says products with an expiry date should not be retested by the purchaser or recipient to extend shelf life. Only in exceptional cases, such as product shortages, should a recipient consider extending the expiry date of received batches, subject to conditions such as scientific data, risk management principles and approval by the national regulatory authority, with the new expiry date reflected on the packaging.¹

Materials given a retest date by the manufacturer, such as chemicals and reagents, are different: WHO says they may be retested and used if the quality parameters are met. Where a manufacturer has obtained national regulatory approval for a new or extended shelf life, that may be applied.¹

What should a manufacturer provide with the shipment?

Clear dates and correct storage. Annex 8 notes that the manufacturing date should be defined by the manufacturer and provided if requested, and section 5.1 says products should be labelled with the expiry, retest or install by date as appropriate.¹ It also says products should be transported, received, stored and distributed in accordance with WHO good storage and distribution practices, with special attention to temperature, light and moisture sensitive products.¹ Shelf life assumes those conditions were kept; see cold chain at the border for the handover points where that is most at risk.

How does this apply to shipments to the Republic of Yemen?

The framework is the one above: a risk assessment, a written agreement, and a clear statement of where delivery is measured. Section 5.1 also says products should meet the policy of the national government as well as the recommendations in Annex 8.¹ The WHO table is an example, not a statement of what any particular country requires. For the Republic of Yemen, the remaining shelf life a recipient will accept is agreed case by case, product by product, and it is worth settling before the first order rather than at the port. For the wider picture of the market, see entering the Yemen market.