OTC-listed Lixte Biotechnology has filed to uplist to Nasdaq, raising $11 million in the process. The uplisting comes as Lixte seeks to accelerate enrollment in a phase 1b/2 myelodysplastic syndrome (MDS) trial that is lagging behind expectations.
Lixte’s lead compound is protein phosphatase 2A (PP2A) inhibitor LB-100. The role PP2A plays in the regulation of processes such as cell division, DNA-damage-response and homologous recombination repair point to the potential of the enzyme as a cancer drug target. However, sporadic efforts to try to treat cancers by drugging PP2A, which date back decades, have failed to establish the target as an important part of the oncology landscape.
As Lixte sees it, the lack of interest in the enzyme stems from a belief that its ubiquity and range of functions will result in intolerable toxicity. In LB-100, Lixte, which has two full-time employees, thinks it has a molecule that is free from that feared toxicity.
n a study of 29 solid tumor patients, two people who received LB-100 suffered dose-limiting toxicity. One in 5 participants experienced grade 3 adverse events that may have been related to the drug.
Lixte emerged from the study with a phase 2 dose and evidence linking the drug to partial responses and stable disease. A phase 1b/2 clinical trial in patients with low or intermediate-1 risk MDS started last year. Lixte plans to hold an interim analysis once 21 of the 41 subjects are enrolled, but is closing in on that target rather slower than hoped.
“Recruitment has been slow and the COVID-19 pandemic has further reduced recruitment of patients into the protocol. At the current rate of accrual, the trial would be completed over a period of four years from its initiation, with the final analysis and reporting expected by July 2023,” Lixte wrote in its Securities and Exchange Commission filing.
To accelerate enrollment, Lixte plans to use additional funds to add two more MDS centers to the phase 2 part of the trial. Lixte expects to have cash reserves of $8.4 million if it hits the midpoint of its stock offering price range.
A Spanish investigator-initiated phase 1/2 trial is in the works, too, but has encountered its own set of problems. Lixte planned to start the trial during the second quarter of 2020, but, having missed that target, ran into a regulatory blockade.
“During July 2020, a Spanish regulatory body advised us that although it had approved the scientific and ethical basis of the protocol, it required that we manufacture a new inventory of LB-100 under current Spanish pharmaceutical manufacturing standards. These regulations were adopted subsequent to the production of our existing LB-100 inventory,” Lixte wrote.
Lixte is still figuring out how soon it can make doses that meet the Spanish specifications, but expects a significant delay. The start of the trial is now penciled in for the third quarter of 2021.