Johnson & Johnson's single-dose COVID-19 vaccine induces strong immunity
Johnson & Johnson's COVID-19 vaccine has shown promise in early-to-mid-stage clinical human trials. The shot, according to the interim results published on medical website medRxiv, was able to generate a strong immune response in the volunteers on both single-dose and double-dose regimen. Plus, it was also found to be safe. Here is all you need to know about it.
Clinical study with over 1,000 volunteers
Officially dubbed Ad26.COV2.S, the J&J vaccine was given to 1,000 healthy adults as part of the Phase-1/2 trial backed by the US government. The study started in July, and now, the results show that 98% of participants - of whom the data was available - had neutralizing antibodies in their blood, 29 days after the vaccination. These antibodies fight off the novel coronavirus.
Questions remain over elderly's immunity
While the data showed that the vaccine produced a strong immune response, its effectiveness on those older than 65, also referred to as the high-risk group, remains in question. This is because the interim data does not offer enough immunity information on them; it just offers data on 15 65+ participants, and to firmly establish efficacy, scientists need more data than that.
Still, there no major adverse effects
On the safety side, the vaccine didn't induce any major adverse effects. Only minor reactions like fatigue and muscle aches were noted, but they occurred less frequently in the elderly group (36%) as compared to younger participants (64%). This led many to assert that the immune response might not be as strong in elderly people, but it is too early to say that conclusively.
Phase-3 trials have already begun
Now, to gain further insight and fully confirm the efficacy and safety level of the J&J shot, scientists are conducting an international Phase-3 study (both single-dose and double-dose) with up to 60,000 participants. The results from this work are likely to come by the end of this year, which would line the vaccine for emergency use authorization by the first half of next year.
