The Swiss drugmaker said on Monday that British health regulators sent it a small number of vials of the counterfeit Avastin to it for analysis.

Roche analyzed three of the vials and found that they contained none of the injectable cancer medicine's active ingredient or any protein or biologic drug, the company said.

What it did find in one or more of the three bogus vials it tested was salt, starch, citrate, isopropanol, propandiol, t-butanol, benzoic acid, di-fluorinated benzene ring, acetone and phthalate moiety.

The contents of the tested vials varied and Roche said it was not able to determine if the compounds or the levels of them would cause harmful or pathological effects.

"The counterfeit product is not safe or effective and should not be used," Roche said in a statement.

The counterfeit Avastin has so far been traced back to Egypt. It passed from there through legitimate distributors in Switzerland, Denmark and Britain before landing in the United States, where U.S. health regulators said it was being sold by shady distributors under investigation for peddling medicines not approved for sale in the United States.

(Reporting By Bill Berkrot)

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