Timing is everything? The drugmaker insists that it was “pure coincidence” that its new ceo, John Johnson, bought $500,000 worth of ImClone stock just days before the value of the shares soared on positive news about Erbitux.

Johnson, a former senior executive at Johnson & Johnson, began work at ImClone on Aug. 27 after signing a four-year employment deal. On Sept. 7, he paid $500,000 for 13,609 ImClone shares at an average price of $36.74 each. The value rose 18 percent, or $6.97 a share, on Sept. 11, when ImClone reported Erbitux prolonged the lives of lung cancer patients in a trial.

“This is 100 percent pure coincidence,” ImClone general counsel Dan O’Connor told Reuters. He that Johnson was required to buy $500,000 ImClone stock within 90 days of the effective date of his employment agreement, and to hold the shares for at least one year after the end of his employment agreement.

“The company believes it is important for a ceo to use his own money to buy stock of ImClone, so he’s not just working with stock option money but using his own funds,” O’Connor argued. “That leaves him standing in the same shoes as his shareholders.”

O’Connor explained that Johnson didn’t have the funds to buy the ImClone shares until Sept. 6, when he received funds owed him by J&J under his former employment contract. “He bought the ImClone stock on Friday, September 7, at the first opportunity after receiving the money from J&J,” O’Connor insisted.

ImClone received the positive Erbitux data on Monday, Sept. 10, via an email from Germany’s Merck KgGA, ImClone’s partner, O’Connor said. “We were surprised to receive them and had no earlier knowledge of whether the results would be favorable or unfavorable until we received them that day,” O’Connor continued.

Stock trades in ImClone in late 2001, based on insider news of a yet-to-be-announced FDA rejection of Erbitux, landed ImClone’s original ceo, Sam Waksal, and his pal, Martha Stewart, in jail. Erbitux was approved two years later with Waksal behind bars.

Viren Mehta, a biotech analyst who runs his own boutique firm, believes Johnson deserves “the benefit of the doubt” about the profitable timing of his ImClone purchases, especially in light of the earlier insider trading scandal at that company.

“This latest study was under the control of Merck in Germany and, generally speaking, study results these days are announced as soon as they become known,” Mehta said. A more plausible explanation, he offered, is that Johnson is on a lucky streak.