Malaria Policy Advisory Group Meeting Geneva, Switzerland 18 October 2017

Transcription

1 Outcomes from Evidence Review Group on data requirements and methods to inform potential extension of WHO policy to new vector control products and to verify performance of products entering an established class Malaria Policy Advisory Group Meeting Geneva, Switzerland 18 October 2017

2 Background WHO process for evaluation of vector control tools, technologies & approaches recently revised Evaluation pathway determine by whether part of a product class with an existing WHO policy recommendation for use Two pathways: 1) Prequalification pathway: products covered by existing WHO policy recommendation 2) New Intervention pathway: all new tools, technologies & approaches supported by Vector Control Advisory Group (VCAG)

3 Vector control product pathway Product Class: A product class in vector control is a group of products that share a common entomological effect by which it reduces pathogen transmission and thus reduces infection and/or disease in humans. A product class may contain one or more target product profiles (TPPs) depending on the intended effect of the product(s) and claim(s).

4 Vector control product pathway

5 2017 ERG objectives ERG convened from September 2017 Tasks: Consider four selected new vector control products as casestudies : SumiShield 50 WG: IRS product containing clothianidin (neonicotinoid-based formulation) a new chemical active ingredient (AI). Pyrethroid-PBO nets: 5 net products evaluated under WHOPES based on classification as pyrethroid LLIN Larvasonic SD-Mini device: new device that emits underwater sound pulses resulting in larval death Fludora Co-Max EW: first space-spray with a mixture of two AIs (flupyradifurone - a neonicotinoid - and transfluthrin - a pyrethroid) Review summarised laboratory and field trial data for each Develop product-specific policy recommendations and general recommendations to support the evaluation process

6 ERG conclusions & recommendations SumiShield 50 WG This meets the current WHO efficacy criteria for IRS products (based on review of mortality data for fully susceptible mosquitoes) Has a similar entomological effect to other IRS products currently covered by a WHO policy recommendation Therefore recommend that existing WHO policy recommendation for IRS should be extended to include SumiShield 50 WG. Any other neonicotinoid insecticide required to demonstrate minimum efficacy criteria for IRS National malaria control programmes and partners should consider deploying SumiShield 50 WG and encouraged to collect data on epidemiological impact through deployment SumiShield 50 WG cannot currently be recommended for insecticide resistance management as only assessed as IRS product

7 ERG conclusions & recommendations General recommendations (1) 1. New IRS, space spray & larvicide products should be considered as covered by existing product classes if they: a) Have the same entomological effect as products is classes covered by WHO policy b) Meet the WHO efficacy testing criteria for the relevant product class, even if their biochemical mode of action differs 2. New IRS, space spray & larvicide products that do not meet current WHO testing criteria need to be assessed by VCAG to determine public health value 3. New LLIN products that are not covered by an existing WHO policy need to be assessed by VCAG to determine their public health value

8 ERG conclusions & recommendations General recommendations (2) 4. New vector control products that have the same biochemical mode of action & entomological effect as a product in a class covered by WHO policy should: a) Meet current testing criteria for the product class based on laboratory, small-scale field trials and large-scale field trials with entomological endpoints b) Demonstrate non-inferiority to at least one existing product by means of small-scale field trials (e.g. experimental hut studies). This comparator should be current best practice used by the national programme. c) For pyrethroid-pbo nets, a set of criteria need to be defined for PBO persistence over time to ensure not only retained by also replenished and bio-available in the surface fibres

9 ERG conclusions & recommendations General recommendations (3): to support work with the aim to refine or modify current evaluation procedures Assessment of non-inferiority of products within a class: recommend in-depth assessment of existing trial data & statistical methods to provide specific guidance Review design, execution & reporting of entomological field trials to develop additional guidance to support high quality studies & standardized reporting Investigate relationship between entomological outcomes from laboratory & small-scale field studies with entomological and epidemiological outcomes from CRTs to determine whether reliable entomological surrogates can be established Encourage multiple comparisons of products of different chemical classes in small scale field studies (e.g. experimental huts) to identify appropriate comparator for large-scale field trials

10 ERG conclusions & recommendations General recommendations (4): further generation of evidence For IRS products, recommend that evidence for 80% mortality following 72 hour holding period should be considered in product assessment Request a review of policies for space sprays and larvicides/larvicidal devices to guide the generation of additional evidence to determine their public health value and hence provide evidence-base to support continued use given current paucity of evidence Space sprays: current test methods should be reviewed to ensure products demonstrate efficacy against wild mosquitoes WHO should update all test guidance to include testing in laboratory studies against resistant mosquito strains including all major mechanisms Encourage development and evaluation of products explicitly designed to control insecticide-resistant mosquitoes