Biotech earnings were mixed midweek, but sector indices held up despite a few sagging stocks.

Onyx ( ONXX) shares closed down $1.48, or 3.7%, at $38.36 on Wednesday. The company reported its quarterly results Tuedsay after the close, beating on EPS by a penny and surpassing revenue expectations. However, Wall Street viewed the company's new Nexavar sales guidance as underwhelming. The company guided to sales of $660 million to $675 million, up from $600 million to $650 million. Wall Street analysts had expected anywhere from between $650 and $700 million.

Meanwhile, BioMarin ( BMRN) gave up $1.60, or 5.0%, to $30.10 and analysts dropped their price targets for the stock a day after it presented second quarter results. BioMarin's phenylketonuria (PKU) drug Kuvan registered $12 million in second-quarter sales, falling short of the $14.8 million consensus. And BioMarin scaled back the top end of its guidance for Kuva revenue by $5 million to $65 million.

On the postive side, sales of its Naglazyme rose 68% to $35.1 million, surpassing expectations for $29.7 million, and the company boosted overall revenue expectations for 2008.

Another stock in the red on midweek, Medarex ( MEDX) reported a widened quarterly loss and revenue below targets. The company reported a loss of $53.1 million, or 42 cents a share, vs. a loss of 32 cents a share a year prior. Factoring out one time charges, the company said it lost 34 cents a share for the quarter. Analysts polled by Thomson Financial expected a loss of 35 cents per share on revenue of $12.5 million.

Its shares gave up 92 cents a share, or 9.3%, to $9.02 on Wednesday.

Onyx, BioMarin and Medarex are all components of the Nasdaq biotechnology index, but gains elsewhere kept it up by 3.25, or 0.4%, at 919.13.

One component faring better, Albany Molecular Research Inc (AMRI) ( AMRI) shares rose $2.66, or 17.6%, at $17.77. The company reported net income of 18 cents a share, or 24 cents a share factoring out a restructuring charge, on revenue that increased 17% to $57.9 million. Contract revenue for the discovery services segment and development/small scale manufacturing segment climbed 54% and 43%, respectively.

Looking ahead, AMRI sees contract revenue of between $186 and $190 million for 2008 and upped its guidance to between 48 cents and 52 cents a share, from between 38 cents and 42 cents a share.

Another stock in the green, clinical research organization Kendle ( KNDL) beat second quarter targets and then upped its 2008 profit guidance to between $2 and $2.15 a share from between $1.90 and $2.07 a share. The company also increased its expectations for service revenue by $40 million to a range of $490 and $500 million a share. Its shares traded up $4.76, or 11.72%, to $45.36.

In analyst actions, Canaccord Adams downgraded biotechnology company Exelixis ( EXEL) to hold from buy. Also, Lazard lowered its price target for the stock to $10 from $12.

Exelixis shares traded $1.14, or 16.0% lower, at $5.97 the first trading day after its quarterly earnings release.