Wedbush Securities upgraded its rating on shares of Anthera Pharmaceuticals, Inc. (NASDAQ: ANTH) to outperform from neutral based on valuation. The brokerage raised its fair value estimate to $8 from $7.

Anthera announced Thursday that interim data showed a statistically significant B-cell reduction among systemic lupus erythematosus (SLE) patients administered A-623 in the ongoing PEARL-SC study.

Anthera said a pre-scheduled interim biomarker analysis of the ongoing PEARL-SC study showed that A-623 was associated with a statistically significant reduction in B-cells compared to placebo.

We recalled that PEARL-SC is a randomized double-blind Phase 2b study evaluating monthly and weekly subcutaneous A-623 for SLE with a primary endpoint of clinical improvement according to the SLE responder index at 24 weeks, said Duane Nash, an analyst at Wedbush Securities.

In addition, Nash recalled that A-623 is an inhibitor of B-cell activating factor (BAFF), and B-cell proliferation is associated with SLE.

While there is strong evidence to suggest that lowering B-cell activity is key to treating SLE (demonstrated by Human Genome Sciences Inc.'s (HGSI) Benlysta), the lupus drug development space is littered with failed treatments that have reduced B-cells but did not demonstrate significant improvements in SLE disease activity (examples are Rituxan and Atacicept).

As such, Nash awaits the full PEARL-SC clinical outcomes data, which the company reiterated will be announced in the second quarter of 2012. Moreover, a PEARL-SC interim efficacy analysis may be performed in the first quarter of 2012.

As such, we view reduction in B-cell as necessary but not by itself sufficient for therapeutic success, suggesting that the recent news is a mild/moderate positive, said Nash.

Nash estimates the near-term milestones for Anthera that include: Varespladib/A-002 DSMB interim efficacy analysis (VISTA-16) in the fourth quarter of 2011; Varespladib/A-002 385th (and final) MACE (VISTA-16) in the first quarter of 2012; possible PEARL-SC interim efficacy analysis in the first quarter of 2012; top-line VISTA-16 data in the second quarter of 2012; and PEARL-SC final efficacy data in the second quarter of 2012.

Shares of Anthera Pharmaceuticals closed Thursday's regular trading down 0.52 percent at $5.79 on the NASDAQ Stock Market.