London's top market shrugged off early pessimism on Wednesday as traders again relished another piece of positive news from one of the world's biggest drugmakers.

Pfizer said that its vaccine, which seemed last week to cure the markets before it inoculated any people, is actually better than first revealed.

The vaccine is 95 per cent effective, Pfizer said on Wednesday, more than a week after saying that initial results indicated 90% efficacy – making it the most effective of the two major vaccines to present results.

Unlike its initial reveal, this was hardly a show-stopping announcement, but enough to give traders a shot in the arm.

The FTSE 100 was up by 19.91 points when markets closed, a 0.3% rise that left it at 6,385.24.

It matched small, but consistent rises in some of Europe and North America's other big indexes.

"While lacking the same pizazz as previous vaccine updates, Pfizer's latest titbit helped heft the markets a bit higher on Wednesday," Spreadex analyst Connor Campbell said.

"Bar the progress report from something like the AstraZeneca-Oxford trial, this might be where we are at for the next few sessions at least in regards to vaccine news: small, reassuring headlines rather than explosive reveals.

"The next major steps, ie those that could reignite the market's recent rally, will be confirmation of FDA approval – which Pfizer is seeking 'within days' – and then a rollout date stateside, and around the rest of the world."

The Dax index closed 0.52% higher in Germany, exactly the same as the Cac in France, while across the pond, the Dow Jones was trading 0.23% higher a little after markets closed in Europe, while the S&P 500 was also up 0.23%.

SSE notched up one of the best days on the FTSE 100, despite revealing a 26% profit dip in the first half of the year. Traders were likely reacting to the £115 million hit from Covid-19 that the electricity giant revealed, which was lower than expected. They sent shares up 4.4%.

But the biggest news of the day also produced the biggest upwards move on the FTSE, as RSA Insurance struck a £7.2 billion deal which will see it split in two parts which will be bought by Denmark's Tryg, and Canada's Intact Financial Corporation. Shares rose 4.6%.

Lloyds Banking Group confirmed that it would restart plans to close 56 branches across the country. It's shares were flat on Wednesday.

British Land's shares took a tumble, dropping 2.4% after it cut the value of its retail portfolio by 15%, while Halfords shares fell 4.6% despite saying that its profits increased in the last six months as Brits bought more bikes.

The biggest risers on the FTSE 100 were RSA Insurance, up 29.8p to 676.8p, Taylor Wimpey, up 7p to 166p, SSE, up 59p to 1407p, Aveva, up 144p to 4254p, and IAG, up 5.35p to 158.8p.

The biggest fallers on the FTSE 100 were Hargreaves Lansdown, down 89.5p to 1526p, DCC, down 296p to 5582p, Homeserve, down 63p to 1204p, Spirax-Sarco, down 450p to 11465p, and Compass Group, down 44.5p to 1346p.