Updated from 2:49 p.m. EDT

Health stocks were stagnant Friday as the FDA asked for more from Amgen's ( AMGN - Get Report) anemia drugs, Bristol-Myers Squibb ( BMY - Get Report) recovered from Thursday's guilty plea, and others reported mixed earnings.

An advisory committee for the Food and Drug Administration said on Friday that Amgen and Johnson & Johnson ( JNJ - Get Report) should be required to add more information to warning labels for injectable drugs that are approved to treat anemia related to chemotherapy and chronic kidney-disease. The agency also ordered the companies to conduct additional clinical studies. Amgen was downgraded by Citigroup and Lazard Capital from hold to sell, and by J.P. Morgan and HSBC Securities from overweight to neutral on Friday. Amgen shares fell $1.03, or 1.8%, to $56.30.

Amgen licensed several rights for Epogen, the short-active version of the anemia drug, which is marketed under the name of Procrit, to Johnson & Johnson in the 1980s. Johnson & Johnson was down 23 cents, or 0.4%, to $62.27.

Bristol-Myers said Thursday it will plead guilty to two criminal counts of false statements to a government agency, in order to resolve an antitrust investigation into a patent settlement related to blood thinner Plavix. The company said the maximum fine is $1 million. Shares were up by 36 cents Friday, or 1.2%, to $30.24.

The Amex Pharmaceutical Index, which includes Amgen, Johnson & Johnson, and Bristol-Myers Squibb, was up 2.07, or 0.6%.

Axcan ( AXCA) fell just 34 cents, or 2%, to $17.02 after NicOx, a partner in developing a portal hypertension drug, announced it was ending a phase IIa clinical trial. The companies have agreed not to further pursue the development of NCX 1000 and to terminate the trial.

MannKind ( MNKD - Get Report) reported a wider first quarter loss of $73.1 million, or $1 a share. In the year-ago quarter, at which time there were 23.6 million fewer shares issued, the company lost $43.6 million, or 87 cents a share. The Thomson Financial consensus for the first quarter was a loss of 99 cents. However, the company also announced that it initiated a clinical trial for its second Technosphere insulin product, MKC-253. Shares were down 9 cents, or 0.7%, to $13.32.

Oncology company YM Biosciences ( YMI) was less fortunate. It reported a loss for its third quarter ended March 31 of $8.9 million, or 16 cents a share, compared to $5.8 million, or 13 cents a share, for the same period last year. Revenue increased to $2 million from $700,000 in the comparable quarter last year, but it was balanced by rising operating expenses. The company said expenses were incurred primarily from increased salaries and bonuses for new employees and the termination of several executives since February. Shares were down 6 cents, or 3.3%, to $1.76.

CytRx ( CYTR) narrowed its first-quarter loss to $4.5 million, or 6 cents a share, compared with a loss of $4.7 million, or 7 cents a share, in the same period last year. The company said revenue was $1.6 million for the period, compared to $61,000 in the year-ago quarter, primarily due to a service revenue recognized from a 2006 royalty transaction with the ALS Charitable Remainder Trust. Shares were down 3 cents, or 0.5%, to $4.18.