Panbela Therapeutics Inc.'s (PBLA:NASDAQ) two polyamine inhibitors, ivospemin (SBP-101) and difluoromethylornithine (DFMO), were shown to inhibit multiple myeloma cells in vitro, a published analysis showed, Dr. Jonathan Aschoff, ROTH Capital Markets analyst, reported in a Dec. 4 research note.
"The data demonstrate that these agents as monotherapies have significant anti-cancer effects on multiple myeloma cell lines, which is increased when they are combined," Aschoff wrote.
4,067% return cited
Given the news, ROTH maintained its $25 per share target price on Panbela, currently trading at about $0.60 per share, noted Aschoff.
The difference between these prices implies a remarkable potential return for investors, of 4,067%
The biopharma remains a Buy.
Assessments conducted
Minnesota-based Panbela and the University of Texas MD Anderson Cancer Center evaluated the effects of SBP-101 and DFMO on growth and viability of four multiple myeloma cell lines: NCI-H929, RPMI-8226, ARP-1 and MM.1S. After exposing these to varying doses of the polyamine inhibitors individually and in combination, the researchers measured the effects on cell proliferation, cell viability and the induction of apoptosis, or cell death. The doses used were based on clinical results of trials evaluating these compounds in other malignancies.
Resulting data were published in the November supplemental issue of Blood.
The objective was to determine if intervening at the polyamine synthesis stage would be effective as a multiple myeloma treatment. Investigating this approach is worthwhile because the proto-oncogene MYC, a significant cause of this cancer, influences the polyamine pathway and is tough to target directly.
Findings are positive
The analysis revealed that both of Panbela's polyamine inhibitors decreased proliferation of cells in all four lines, Aschoff reported.
Specifically, as for SBP-101, one of the biopharma's lead assets, test results showed that increasing concentrations of it, from 1−10 micrometers (1−10 µM), significantly reduced cellular proliferation in all cell lines. The average percentages of cytotoxicity observed with SBP-101 10 µM were 84% in ARP-1, 69% in NCI-H929, 49% in MM.1S and 21% in RPMI-8226.
Regarding DFMO, increasing concentrations of it, from 1−100 µM, affected the cell lines like SBP-101 did. However, DFMO impacted RPMI-8226 the most versus ARP-1 with SBP-101. The percent of cell death resulting from DFMO 10 µM was 64% in RPMI-8226, 33% in NCI-H929, 28% in ARP-1 and 16% in MM.1S.
A combination of SBP-101 10µM and DFMO 100 µM completely stopped growth of cells in all lines. Both monotherapy and combination therapy resulted in apoptosis.
Second potential approach
In other news, results of different research by Panbela and MD Anderson suggested that potential exists for a polyamine-targeted therapy in combination with CAR-T therapy.
| Want to be the first to know about interesting Biotechnology / Pharmaceuticals investment ideas? Sign up to receive the FREE Streetwise Reports' newsletter. | Subscribe |
