The Lancet medical journal has published a report of two achievements with encouraging results from Covid-19 phase 1/2 trials at Jenner Institute at Oxford University and another at CanSino Biologics in Wuhan, China.   The emergence of SARS-CoV-2 and the subsequent Covid-19 pandemic triggered the active development of nearly 200 vaccine candidates, said the report on Monday night.   The results of two early phase vaccine trials are reported, one from investigators at the Jenner Institute at Oxford University (Oxford, UK), with support from AstraZeneca, and the second from investigators supported by CanSino Biologics in Wuhan, China.     Both groups used an adenoviral vector, and both report the vaccine achieving humoral responses to the SARS-CoV-2 spike glycoprotein receptor binding domain by day 28 as well as T-cell responses, the Lancet report said.   Both report local and systemic mild adverse events such as fever, fatigue, and injection site pain. In neither trial was a severe adverse event reported, it said.   Andrew Pollard and colleagues report their phase 1/2 randomised trial of one injection of chimpanzee adenovirus-vectored Covid-19 vaccine.   Vaccine formulation at one concentration was tested against a comparator quadrivalent conjugate meningococcal vaccine among 1,077 healthy adults (50 percent male, 90.9 percent white) aged 18–55 years (median 35 years, IQR 28–44), recruited from five centres in the UK and followed up for 28 days.