* FTSEurofirst 300 index up 0.2 pct
* UCB, BNP Paribas, Natixis up after results
* Engie falls on HSBC downgrade to "hold"
By Atul Prakash
LONDON, July 31 (Reuters) - European shares advanced for a fourth straight session to a one-week high on Friday, with forecast-beating earnings reports from some companies underpinning market sentiment.
Shares in UCB surged 5.2 percent, the top gainer in the pan-European FTSEurofirst 300 index, after the Belgian pharmaceutical company raised its 2015 forecasts as sales of its three major upcoming drugs propelled first-half earnings by more than expected.
BNP Paribas gained 3.5 percent after the French bank saw its revenue rising nearly 16 percent in the second quarter, boosted by brisk share trading, a strong dollar and recently acquired companies.
Natixis rose 3.3 percent after reporting a 5 percent rise in net income for the second quarter, driven by a strong increase in asset management, insurance sales and private banking, as well as continued efforts to reduce its balance sheet and risky assets.
"Overall, the results so far have been pretty good, with the banking sector putting in some good numbers as well," said Clairinvest fund manager Ion-Marc Valahu.
According to Thomson Reuters StarMine, nearly half of the STOXX Europe 600 companies have announced results so far, of which 53 percent have met or beaten analysts' forecasts.
On average, 48 percent companies beat analyst EPS (earnings per share) estimates in a quarter. Second quarter earnings are expected to grow by 5.7 percent from the corresponding quarter of the previous year.
The FTSEurofirst 300 index of top European shares was up 0.2 percent at 1,574.12 points by 0736 GMT after rising to a one-week high of 1,575.11 points. The index advanced in the previous three sessions and heads for a positive weekly close after falling last week.
Shares in Airbus was up 4.2 percent after the aerospace group posted a 6 percent rise in first-half core operating profit and revenue, and confirmed its full-year financial forecasts.
Belgium's Engie fell 3.8 percent, the top faller in the FTSEurofirst 300, as HSBC cut its stance on the stock to "hold" from "buy" after the company reported this week that its first-half 2015 profit dropped due to lower gas prices and the unavailability of three of its seven Belgian nuclear plants.
InterContinental Hotels fell 2.7 percent after it denied late on Thursday that it was in talks with Starwood Hotels & Resorts Worldwide Inc with a view to a combining businesses. Its shares had risen in the previous session on a report it had held early talks with Starwood.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up
Additional reporting by Sudip Kar-Gupta; Editing by Dominic Evans