# Presentation: 623503

## PATH’s Experience from Jet Injector R&D and Field Assessment in Developing Countries

- Innovative Administration Systems for Vaccines
- December 18, 2003
- Darin Zehrung

## History of Jet Injector  Development at PATH

- 16 years of in-house design and development experience (MEDiVAX, N-Ject)
- Evaluation and testing of numerous jet injectors
- Portfolio of patents and know-how (needle-free) – US government subject invention
- Collaboration with Felton International

**Notes:**
A portfolio of patents and know how

5,746,714 Air powered needleless hypodermic injector 
5,938,637 Single-use medicine delivery unit for needleless hypodermic injector
6,213,980 Fill facilitating unit dose injection cartridge and filling method 

## MEDiVAX Design: 1988-1997

- Development funded by USAID under HealthTech
- Collaboration with Vitajet
- Low workload injector – routine immunization
- Air powered system (foot pump) – novel design
- Incorporated “spacer” to prevent cross contamination
- Field assessment 1989-1995
- Bench and animal studies demonstrated that cross contamination occurs

- ProtoV

## MEDiVAX Field Assessment

- Indonesia -1992

## MEDiVAX Contamination Testing (1997 PHLS)

- Hoffman PN, Abuknesha RA, Andrews NJ, Samuel D, Lloyd JS.  A model to assess the infection potential of jet injectors used in mass immunisation.  Vaccine 19 (2001) 4020–4027

## N-Ject Design: 1997-1999

- Use of disposable ampules
- Pre-fill or fill on site
- “Filling station” design developed
- High life cycle nitrogen spring (handpiece)
- Project shelved due to the following challenges:
- Performance issues – molded ampule
- Vaccine manufacturer prefill
- Fill on site – sterile transfer
- Necessary development funds not available

## Developmental Tests: 1988-2003

- Evaluation of design iterations
- Baseline/predicate device comparison
- Dosage
- Stream Focus
- Penetration
- Force
- Stream Coherence (video/photography)
- Contamination

- Stream focus – optical comparator image

**Incoherent -**

**Notes:**
In support of Medivax development, as well as to assess predicate devices to establish a baseline of comparison, a series of tests were developed at PATH. These tests provided necessary input and data to influence the development of the Medivax and N-Ject, as well as to provide other device developers tests that they could utilize for their own efforts. Copies of these test procedures were openly shared with device developers in 2000/2001. 

## Development Tests (cont.)

- Stream Coherence – video

- Penetration – tissue simulant

**Notes:**
Penetration:
Can indicate completeness of delivery
Can indicate depth of shot
Evaluates “whole” device performance
Go-no-go challenge- not a simulation of tissue
Correlates to observed completeness of delivery
Uses foam laminates with silicone skin

## PATH Fluorescein Bench Test

- Sensitivity: 2.5 pL per 0.5 cc dose
- Models “ballistic” contamination event
- Bench test intended to inform designers and engineers during product development
- “Worst case” scenario — does not accurately replicate tissue response — represents maximum challenge

**Fluorescein ****positive control sample**

- Injection “wells”

**Notes:**
Utilizes Luminescence Spectrometer

## PATH Product Development Shop

- Tremendous growth over the past 15+ years
- Extensive in-house product development capabilities (injection molding, machining, testing, environmental)

**Notes:**
Starting in 1988, the development shop was simply a drill in a drawer. Over the past dozen plus years, the development shop has grown into a full service research and development shop, with extensive prototyping and testing capabilities. The growth of the shop has mirror the tremendous growth PATH has experienced as an organization. There are multiple projects now currently underway within the shop, to include contraceptive barrier development (silicone diaphragm, woman’s condom), sharps removal technologies, and various other health technologies.

## PATH – Felton International Collaboration

- Project Goals:
- Design and development of a low cost, mass immunization campaign injector suitable for developing country use
- Reversal/modification of current WHO policy to allow for use of the mass immunization campaign injector
- Re-introduction of the campaign injector into developing world

## History of Collaboration — PATH and Felton International: 1998-2003

- PATH project work funded by USAID under HealthTech

## Felton International Campaign Injector

- DESIGN DEVELOPMENT 1998-2002

## Senegal Field EvaluationProtector Cap Injector: September 2002

- Purpose: Human factors evaluation of prototype design
- Focus group sessions/training
- 3 Senegal sites:
- St. Louis
- Richard Toll
- Podor

**Notes:**
Senegal was selected as the country to conduct the field evaluation of the injector for several reasons:
-PATH maintains a program office in Dakar (Children’s Vaccine Program)
-Senegal was soon to implement a mass immunization campaign for measles. The very same personnel interviewed during the field evaluation were subsequently involved in the mass campaign.

This was a ‘mock-use’ evaluation and did not include actual injections into humans.

## Senegal Field Sites

- St. Louis

- Podor

- Richard Toll

## Device Training (1)

- Inspecting the protector caps

- Protector cap placement

## Device Training (2)

- Injection practice with tissue simulant

## Focus Group Discussions

## Richard Toll User Evaluation

## Podor User Evaluation

## Human Factors	

- Dirt in the foot pedal

- Operating the injectors barefoot

- Hand piece difficult to hold

## Human FactorsDevice and Cap Handling

- Simulated injection and loading the protector caps

## Cap Handling

- Protector cap and package management – challenges

## Waste Management

## Outcomes from Senegal Field Evaluation

- Human factors input received prompted redesign of handpiece and footpedal – led to the new “torch” design
- Training will be critical to proper usage and acceptance
- Must address logistical issues such as waste management and field sterilization

## New “Torch” Design – Jet Injector for Mass Immunization

- Felton International

## Jet Injector for Mass Immunization – PATH Strategy

| PHASE | 2004 | 2005 | 2006 | 2007 |
| --- | --- | --- | --- | --- |
| Design/Development |  |  |  |  |
| Human Safety Testing  |  |  |  |  |
| Acceptability |  |  |  |  |
| Replication |  |  |  |  |

- Thank You