Roche’s $46.8 billion takeover of Genentech (DNA) will give the Swiss company control of Avastin and Herceptin  promising cancer treatments. The bet: Results on Avastin’s clinical trials for early stage colorectal cancer will be released soon and if the drug is effective it would drive up Genentech’s value. Roche apparently believes the results will be positive and therefore rushed to complete the deal. Avastin is already approved to treat breast and lung cancer. It generated about $4.8 billion in sales last year and could become a top-selling drug worldwide. In terms of market share the combined company will be ...