Charleston Laboratories said today it has regained U.S. rights from Daiichi Sankyo to its lead product CL-108 (hydrocodone, acetaminophen, promethazine), six months after the FDA derailed the companies’ New Drug Application (NDA) for the acute pain management candidate by issuing a Complete Response Letter (CRL).
The deal—whose value was not disclosed—ends a three-year collaboration between the companies that generated $200 million upfront and could have generated up to $650 million for Charleston Labs.
The collaboration, launched in August 2014, was designed to develop combination hydrocodone drugs for moderate to severe acute pain and opioid-induced nausea and vomiting (OINV).
CL-108 is a fixed-dose, bilayered tablet combining 12.5 mg of immediate-release promethazine with a modified release of 7.5 mg of hydrocodone and 325 mg of acetaminophen. CL-108 is being developed for acute pain patients who require an opioid analgesic while preventing or reducing OINV.
“By addressing OINV, we believe that patients will achieve proper pain relief, shortened recovery time, and fewer days on opioid medication. Through decreasing a patient's use of opioids, we aim to reduce the risk of misuse and abuse,” Paul Bosse, Charleston Labs’ president and CEO, said in a statement.
Charleston Labs said the return of rights will enable the company to centralize its comprehensive acute pain portfolio, and accelerate efforts to bring CL-108 to market.
“We thank Daiichi Sankyo for their partnership, and now with a singular focus, we are excited to rapidly execute our corporate strategy,” Bosse added.
NDA Resubmission Planned
That strategy calls for developing novel pain treatments designed to reduce side effects related to opioid analgesics and other products. In addition to OINV, Charleston Labs aims to treat migraine-associated nausea and vomiting (MANV).
On February 6, Charleston Labs and Daiichi Sankyo acknowledged that the FDA issued a CRL for their CL-108 NDA, which sought approval for an oral tablet form of the drug, but did not disclose the agency’s concerns that led to the letter.
Today in its statement, Charleston Labs said it will resubmit the NDA for CL-108 “in the coming weeks.”
The NDA had been supported by positive results from two Phase III clinical studies—one following oral surgery (molar removal), the other after bunionectomy surgery—as well as a third Phase III open-label, actual use safety study in patients with moderate-to-severe acute pain, or “flares,” associated with osteoarthritis of the knee or hip. More than 1000 patients were enrolled in the CL-108 Phase III clinical trial program.
In the oral surgery trial, 34.6% of patients (211) treated with CL-108 reported moderate or severe nausea, compared to 60.5% of patients (205) treated with hydrocodone and acetaminophen (HC/APAP) alone. The incidence of vomiting was 13.3% for CL-108-treated patients, compared to 26.3% for HC/APAP-treated patients, according to a Charleston Labs-funded study presented at last year’s American Academy of Pain Medicine (AAPM) Annual Meeting.
A human abuse liability study has also been conducted, according to Charleston Labs.