The FTSE 100 held onto earlier gains in response to the seemingly positive vaccine news from Pfizer, ending the session up 4.9% at 6,198 points, while Pfizer shares were 9% ahead in morning US trading.
There were wild price swings as formerly unloved stocks surged and former 'safe havens' were aggressively sold off.
On the FTSE 250 mid-cap index, shares in embattled cinema operator Cineworld (CINE) jumped 40%, followed closely by high-street retailer WH Smith (SMWH) and food producer Greencore (GNC) with gains of 38% and 37%.
House builder Taylor Wimpey (TW.) said it expects to end the year with a net cash balance towards the upper end of its guidance after 'robust' sales in the second half, according to its trading statement.
The company projected it would end 2020 with a net cash balance towards the upper end of its guidance of between £550 million and £750 million, above the cash balance £545.7 million at the end of 2019 - subject to the timing of conditional land purchases. Shares jumped 18% to 145.87p.
Shares in UK and US bus and rail company First Group (FGP) rallied 17.2% to 53p after it announced it had agreed covenant amendments for the 31 March and 30 September 2021 testing dates with its lenders.
The prior net debt to EBITDA (earnings before interest, taxes, depreciation and amortisation) level of 3.75 times has been increased to 5.5 times and 4.5 times for the March and September tests respectively.
Encouragingly, the firm also said it expected to report a small adjusted operating profit in the first half, which was ahead of its previous base case scenario.
The total return of the shares for the three-month period to 30 September 2020 was 20.6%, giving a year-to-date return of 11.8%. Shares added 1.2% to 305.5 p.
Shares in specialist international distribution and services group Bunzl (BNZL) dropped 3.4% to £24.65 after it agreed to acquire SP Eqipamentos, a leading personal protection equipment distributor based in Brazil.
SPE generated revenues of £22 million last year, and the deal is expected to complete by the end of the month.
Ultra Electronics Holdings (ULE) reported its operating margins are slightly better than expected due to lower indirect costs related to the Covid-19 pandemic and robust core defence markets.
In a trading update on its performance over the nine months to 30 September 2020, the company said order intake remains strong with good revenue growth, as anticipated. Shares lost 1.9% to £20.2.
UK DRUG NEWS
GlaxoSmithKline's (GSK) specialist HIV company ViiV Healthcare reported that interim analysis from the HPTN 084 study shows long-acting injectable cabotegravir administered every two months is 89% more effective than daily pills in preventing HIV in women.
This follows data from another study in men who have sex with men and transgender women which also demonstrated that cabotegravir was superior to oral pills. Shares added 2.2% to £14.3.
AstraZeneca (AZN) said its drug Calquence had received European Union approval for the tatment of adult patients with chronic lymphocytic leukaemia (CCL) adding to approvals already received in the US and several other countries worldwide.
In Phase three trials Calquence combined with obinutuzumab and as a monotherapy reduced the risk of disease progression or death by 90% and 80% respectively compared with standard treatments. Shares lost 1.5% to £83.8.