^{Monthly medical update – Issue 2}

^{4 September 2020}

By Nicola Oliver and Joseph Lu for

Nicola

Jo

COVID-19 Actuaries Response Group – Learn. Share. Educate. Influence.

Given the pace of change with ‘all things COVID’, it can be hard – even for those who follow all the updates – to know what the overall state of play is regarding medical developments in particular, as opposed to just the most recent news.

In this new type of Bulletin, we provide a summary of what we believe the current medical position to be. We will aim for these summaries to be accurate as at the date of publication but they will of course date rapidly, so we plan to issue an updated summary each month.

Vaccines

As at 3 September 2020, the following potential vaccines were in clinical trials[1]:

In addition, there around 140 preclinical trials in progress for vaccines to tackle SARS-CoV-2.

Clearly, the vaccines in the more advanced stages of clinical trial development hold the most promise. The compound under investigation by the University of Oxford has demonstrated the ability to provoke both an antibody and T-cell response. However, the durability of this response is still unknown. Results from the larger phase 3 trials will shed more light on its potential success.

A candidate vaccine developed by U.S. biotech company Moderna and the National Institute of Allergy and Infectious Diseases (NIAID) was the first to be tested on humans in the U.S.. Results from this ongoing study also report evidence of neutralizing antibodies in participants.

The compound being developed by CanSino Biologics, in collaboration with the Beijing Institute of Biotechnology, has also demonstrated promising results. The study has reported that around 90% of the participants developed T-cell responses and about 85% developed neutralizing antibodies, according to the study.

Treatment

• Corticosteroids have been shown to be effective in severely ill patients hospitalised with COVID-19 who are receiving mechanical ventilation. A recent prospective meta-analysis of clinical trials of critically ill patients with COVID-19 concluded that administration of systemic corticosteroids, compared with usual care or placebo, was associated with lower 28-day all-cause mortality. (steroids)
• Results from trials using the antiviral drug remdesivir indicate that patients who received remdesivir had a 31% faster time to recovery than those who received placebo. A phase 3, randomized, open-label trial showed that remdesivir was associated with significantly greater recovery and reduced odds of death compared with standard of care in patients with severe COVID-19. (remdesivir)

Testing

• There are currently two types of diagnostic test available. The molecular real-time polymerase chain reaction (RT-PCR) test detects the virus’s genetic material, and the antigen test detects specific proteins on the surface of the virus.
  • RT-PCR tests are almost 100% accurate if carried out correctly.
  • Antigen tests are less accurate but have a faster turnaround, potentially under one hour. However, false-negative results from antigen tests may range as high as 20-30%
• Antibody tests are not diagnostic tests and are used primarily to identify whether you’ve recovered from COVID-19. Antibody tests also are subject to false-positive results. Research suggests antibody levels may wane over just a few months. And while a positive antibody test proves you’ve been exposed to the virus, it’s not yet known whether such results indicate a lack of contagiousness or long-lasting, protective immunity.
• Unfortunately, it’s not clear exactly how accurate any of these tests are. Development in all test types is ongoing.

Antibodies

• There is emerging evidence that those who have previously been confirmed positive for COVD-19 may not develop a sustained antibody response and are susceptible to reinfection.
• Several cases have been reported (reinfection); this has implications for vaccine development and strategies to contain the virus.

[1] https://www.who.int/publications/m/item/draft-landscape-of-covid-19-candidate-vaccines