Janney Capital analyst Ken Trbovich noted that the FDA, in a warning letter to Porton Biopharma, said that the supplier failed to adequately address ongoing particulate contamination issues with Erwinaze, while also raising issue with changes in cell banks. Jazz cannot control PBL's actions, but it is responsible for ensuring the product it markets and distributes, said Trbovich, who added that the issue of a change in cell banks is a "far more significant problem" than the particulate contamination. If Jazz removes, or the FDA blocks, Erwinaze from the market, it may lead to reductions in estimates, fair value and Jazz's rating, added the analyst, who keeps a Neutral rating on Jazz shares.