Cytokinetics ( CYTK) retreated after the South San Francisco, Calif.-based biopharmaceutical company said an interim analysis following the first stage of a two-stage phase II clinical trial for Ispinesib, its treatment for recurrent and metastatic head-and-neck squamous-cell carcinoma, determined that the drug did not satisfy the criteria for advancement to Stage 2. The best overall response to date in the clinical trial was disease stabilization, the company said, which was observed in five of 19 patients. Ispinesib is being developed in collaboration with GlaxoSmithKline ( GSK). Shares of Cytokinetics were trading down 52 cents, or 8.19%, to $5.83. CKE Restaurants ( CKR) gained after Standard & Poor's said the Carpinteria, Calif.-based restaurant chain will replace Ryan's Restaurant Group ( RYAN) on the S&P Small-Cap 600 after the close of trading on Thursday. Ryan's is being acquired by Buffets Inc. in a deal expected to close on or about that day, Standard & Poor's said. Shares were climbing 43 cents, or 2.57%, to $17.15. Bright Horizons Family Solutions ( BFAM) rose after Standard & Poor's said the Watertown, Mass.-based company will replace FileNet ( FILE) on the S&P Small-Cap 600 after the close of trading on a date to be announced. FileNet is being acquired by IBM ( IBM) in a deal awaiting final approval. Shares were climbing 77 cents, or 1.91%, to $41.06.