Clinical trials – the role of volunteers in developing safe and effective vaccines

Written by Results Policy & Advocacy Manager, Mark Rice.

Since early February, I have been a participant in a clinical trial for a potential oral COVID-19 vaccine. As we highlight the importance of vaccines during World Immunisation Week (24-30 April), I am sharing my experience to highlight how clinical trials are important in the development of safe and effective vaccines.

The development of COVID-19 vaccines has occurred at a rapid pace, taking approximately one year from initial research to wide usage. Previously, the process for vaccine development could take up to 10 years from early research to wider usage. However, any approved vaccine has been through a series of trials explained below, and my experience reinforces that researchers developing vaccines aim to minimise any adverse impacts in the trial participants, and of course minimise the risk of any harm from the vaccines in use.

Clinical trials are crucial in ensuring that new vaccines are both effective and safe but can only be possible if people are willing to volunteer and participate in the trial.

To ensure everyone has access to free or cost-effective vaccines, we need more vaccine research. In the current scenario, “For everyone on this planet – or at least 90% – to get it, it’s going to be at least 2024,” says Adar Poonawalla, CEO of the Serum Institute of India that is currently producing the Oxford/AstraZeneca vaccine. It is therefore critical to continue vaccine research and trials in our quest for more effective and low-cost vaccine alternatives. I am very glad that I am part of the oral vaccine trial which if successful can be a strong alternative.

The other concern is the public perception that COVID-19 vaccines are rushed. Experts confirm that the process has been sped up and not skipped. From my experience, as a participant, I was satisfied with the steps taken to ensure safety of the vaccine. As a public health professional I consider this an essential and should be the benchmark for future vaccine development.

Stages at which we can be involved: The different stages of clinical trials, which any vaccine approved for use needs to go through, are:

Phase 1: At this stage, a new vaccine or treatment is tested on a small group of people (usually 20-80) to evaluate factors such as safe dosage amounts and possible side effects. I have been a participant in a phase 1 trial, which involves weekly check-ups following the receipt of each dose of the trial vaccine, and identifying any symptoms or reactions I experience each day, whether they would be linked directly to the trial vaccine or not. After two months, the monitoring of any conditions or symptoms is less frequent, although I have some follow-up appointments to assess any longer-term impacts.

Phase 2: At this stage, the new vaccine or treatment is tested with a larger group of people (several hundred) to determine whether the measure works as intended and to further evaluate its safety.

Phase 3: At this stage, a new vaccine or treatment is tested with a large group (from several hundred to several thousand) and compared to other standard or experimental measures to see how effective the measure is and identify any adverse effects. Following this stage, a measure can be ready for introduction with the general population.

Phase 4: Studies at this stage assess the effectiveness of a measure when it is in use, and also if the vaccine or treatment may have additional benefits or uses (eg, on other conditions).

Why trial volunteers are important: As one of the nurses administering the trial vaccine to me noted, researchers can only learn some of the likely effects of a new vaccine or treatment from computer simulation and animal testing, and nothing can substitute for testing on humans.

Therefore, while a person participating in a trial is taking some risks in receiving an experimental vaccine or treatment, and makes a commitment of time to attend check-ups and to monitor and record any symptoms, the reward is people like me are contributing to the development a vaccine or treatment that could prevent illness or even death for millions of people.

Vaccine development and distribution

Developing a market ready vaccine doesn’t automatically ensure that it reaches everyone in need and that everyone is willing to take a jab. Of course, there are several other actions which are required:

• Supporting all countries to obtain supplies of and have the capacity to administer the vaccines that are available. In the case of COVID-19, this means providing additional support to equitable distribution of vaccines among countries through investing in the COVAX facility. Donor countries including Australia pledged their support to COVAX and additional funding to support countries in need. Australian government pledged $500 million to support COVID-19 vaccination in the Pacific and South-East Asia leads to a safe and widespread availability of vaccines in the region.

• Fragile health systems, overburdened health staff and machinery need technical assistance in rollout and delivery of vaccines.

• Providing assistance to increase the capacity of health systems so countries can provide vaccines in the locations most in need and integrate vaccination with other health services.

The importance of both the vaccine development and distribution stages is a reminder that everyone has a role to play in achieving the goal set out in the theme for World Immunisation Week this year – Vaccines Bring Us Closer.