Product description

This is a generic product specification for a long lasting residual formulation for Indoor Residual Spraying (IRS) programs to improve malaria and dengue vector control in Disease Endemic Countries (DECs).

The product must be able to pass the WHOPES minimum threshold for IRS a minimum of 6 months after spraying, preferably after 12 months.

The products developed within this specification should ensure that all currently recommended WHOPES active ingredients are developed as long lasting formulations as a minimum.  Any active ingredients not currently included in WHOPES should have risk assessments that would allow their use in IRS.

Currently only DDT WP 750 has a substantiated label claim of 9-12 months residuality.  The development of more insecticidal classes as long lasting formulations will enable the malaria and dengue control programmes to manage the potential development of resistance more efficiently by using the different classes in rotation and thus delay the development of resistance.

These long lasting IRS formulations should only have to be sprayed once a year in DECs.  The new formulations will reduce the cost and logistical problems associated with IRS. Long lasting formulations would allow a reduction in the number of application rounds per year, significantly decreasing the application cost. The reduction in cost achieved would reduce IRS treatments to similar operational costs as current insecticide treated material.


Essential Product Characteristics

Required performance or efficacy

The minimum Target Product Profile (TPP) is to obtain a sprayable formulation that will match the efficacy profile of the current WHOPES recommended formulations on most standard wall surfaces (eg: mud, concrete, plaster, plywood, etc) against malaria vectors, but with a residuality of a minimum of 6 months and a target of 12 months. Using the WHOPES threshold for IRS residual activity, the TPP is >80% mortality after 30min exposure to the treated surface (and 24h holding period) at least 6 months after application.

The formulation should be capable of application using a standard Hudson sprayer with normal nozzle technology.

Cost of implementation in the field
It is a prerequisite of the global access plan that the product should be affordable and competitively priced for target populations in disease endemic countries. The health economics cost/benefit assessment would take into consideration not only the cost of the product but its cost-effectiveness in reducing malaria/dengue (as shown in phase III trials), the much longer residual activity and reduced operational costs and its capacity to stop resistance being selected.  The total cost of a long lasting IRS formulation must be competitive for the product’s insecticide class.  Although the product cost can be higher than the standard formulation for its class, it must offer an overall programme cost benefit.

The product will be benchmarked against the current costs for other IRS formulations on the market.  This will be reviewed at key milestones.    

Safety and regulatory profile
The active ingredients used must meet WHOPES risk assessment standards for IRS.  An initial positive risk assessment for the active ingredients must be submitted with the proposal for review and comment by the IVCC ESAC toxicology, eco-toxicology and risk assessment professionals.

A full standard regulatory package will be developed for the long lasting residual formulation once the formulation technology has been confirmed. As part of this package information on the efficacy, safety and acceptability of the product shall be submitted in accordance with the WHO ‘Guidelines for testing mosquito adulticides for indoor residual spraying and treatment of mosquito nets. WHO/CDS/NTD/WHOPES/GCDPP/2006.3.’  The dossier will be submitted to the appropriate regulatory authority, including WHOPES, for registration against internationally accepted criteria.

The active ingredients used must be registered for use in at least one major regulatory authority (EPA, EU or Japan) for a crop protection or vector control application.

Suitability for end users
The long lasting formulations should have no features that cause end users to oppose their use, e.g. they should leave no visible residue, there should be no lasting adverse odour etc.

Manufacturing considerations
The final formulation needs to be suitable for manufacture in an existing manufacturing plant and be produced in easy to use packaging. The active ingredients need to be freely available to the company developing the product.

IP issues
There should be freedom to operate from any existing patent. All background and foreground IP should be freely made available for the product’s development and use in vector control in disease endemic countries.

Desirable Product Characteristics