Johnson & Johnson (NYSE:JNJ) said its vaccine candidate was found to be 66% effective in preventing moderate to severe COVID-19, 28 days after vaccination.
Unlike all other COVID-19 jabs already in circulation, it only needs to be administered with one shot which makes rollouts easier, though it fell short of its competitors in terms of efficacy.
READ: What sets Johnson & Johnson’s vaccine apart from those already in circulation
The results come from interim analysis of late-stage trials, which so far have involved 43,783 participants with 468 symptomatic cases of the disease.
The level of protection was 72% in the US, 66% in Latin America and 57% in South Africa, with the onset observed as early as day 14.
The first batches are hoped to be ready for emergency authorisation early this year, with J&J scaling up capacity to produce 1bn doses each year.
The formulation is developed the group’s Belgian arm Janssen’s AdVac technology, which uses a genetically modified version of the common cold virus (adenovirus) so it can no longer replicate in humans and cause disease.
It can remain stable for two years at -20°C and at least three months at 2-8°C, so it’s compatible with standard distribution channel without the need for extra infrastructure.
Shares dropped 4% to US$162.95 in pre-market trading.