Investors who backed a biotechnology company led by executive Martin Shkreli are suing to get back the $5.4 million they had invested just hours before his arrest, according to court papers. Shkreli took control of KaloBios Pharmaceuticals Inc in November, saving the company from closing down. As part of Shkreli’s rescue, the company reached a deal with three individuals and two funds to invest $5.4 million in it under an agreement that KaloBios said was completed on Dec. 16.