Updated from 8:13 a.m. EDTImClone Systems' ( IMCL) second-quarter earnings rose 43% from a year ago, helped by higher royalty revenue from the sale of anticancer drug Erbitux by partner Bristol-Myers Squibb ( BMY). ImClone earned $37.2 million, or 42 cents a share, in the quarter, compared with $26 million, or 30 cents a share, a year ago. The latest quarter had a charge of 2 cents related to new accounting. Analysts were forecasting earnings of 38 cents a share in the most recent quarter, according to Thomson First Call. Sales were $149.9 million, up from $92.4 million a year ago. Analysts had been forecasting sales of about $142 million. ImClone collected royalty revenue of $74.6 million this quarter, up from $41.8 million a year ago, and saw manufacturing revenue grow to $28.4 million from $7.9 million. "Royalty revenue for the second quarter of 2006 includes 39% of Bristol-Myers Squibb's in-market Erbitux net sales of $172.8 million, compared with second-quarter 2005 in-market net sales of $97.9 million, an increase of 77%," the company noted Thursday. ImClone declined to provide a breakdown of Erbitux sales for specific indications or comment on its market expectations. However, the company did say the number of patients in the second quarter being treated with the drug for colorectal cancer increased, and added that there's significant room for Erbitux to grow as a treatment for head and neck cancer. Erbitux could be facing competition in the not-too-distant future from panitumumab, a drug Amgen ( AMGN) is hoping to have cleared by the Food and Drug Administration. Panitumumab is designed for colorectal cancer but it has been studied as a potential head and neck cancer treatment, as well. ImClone also received license fees and milestone revenue of $33.5 million compared with $24.5 million a year ago. Revenue from collaborative agreements declined to $13.4 million from $18.2 million owing to a reduction in shipments to its European marketing partner Merck KGaA. ImClone shares fell 4.9% to $36 recently.