Plus Therapeutics, Inc. · NASDAQ:PSTV
Plus Therapeutics — Technical Presentation (June 2024)
19 slides from Plus Therapeutics's technical presentation, June 2024
Slide 1: Radiation Absorbed Dose to Spinal Cord: Therapy of Leptomeningeal Metastasis
SNMMI Annual Meeting 2024, Toronto, Canada Radiation Absorbed Dose to Spinal Cord: Therapy of Leptomeningeal Metastasis Using Beta-Emission Radiopharmaceuticals Ande Bao1, Xia Zhao1, William Phillips2, Andrew Brenner2, Michael Youssef3, Priya Kumthekar4, Jonathan Yang5, Yiran Zheng1, Daniel E. Sprat
Slide 2: Disclosure
Disclosure + Ande Bao, William Phillips, and Andrew Brenner are share holders of NanoTx, Inc. + Norman LaFrance, Melissa Moore, Andrew Brenner, and Marc Hedrick are employees of Plus Therapeutics, Inc. + Ande Bao and William Phillips are also consultants of Plus Therapeutics, Inc. + Grant support: C
Slide 3: Leptomeningeal (LM) Metastasis of Cancer
Leptomeningeal (LM) Metastasis of Cancer + LM metastasis or LM disease is a malignant development of cancers. It involves in the metastatic spread of cancer cells in the meninges of brain and spinal canal. + LM metastasis occurs in 5 – 15 % of patients with malignant cancers, including breast cancer
Slide 4: Radiation Therapy of LM Metastasis
Radiation Therapy of LM Metastasis Proton Therapy Craniospinal proton radiation therapy, which treated the entire central nervous system (CNS) compartment with proton beam. The median CNS PFS was 7 months (95% CI: 5–13) and the median OS was 8 months (95% CI: 6 to not reached). Four patients (19%) w
Slide 5: Therapy of LM Metastasis using Therapeutic Radiopharmaceuticals
Therapy of LM Metastasis using Therapeutic Radiopharmaceuticals Therapeutic radiopharmaceuticals have also been studied in the treatment of LM metastases via locoregional administration, e.g. 131I-labeled antibody. An active undergoing clinical trial is in progress with the use of 186Re-nanoliposome
Slide 6: Therapy of LM Metastasis using Therapeutic Radiopharmaceuticals
Therapy of LM Metastasis using Therapeutic Radiopharmaceuticals + The use of therapeutic radiopharmaceuticals provides a focused radiation field to eradicate the cancer cells in the meninges and in the leptomeningeal-spinal fluid. Comparing with external beam radiation therapy (EBRT), a higher radia
Slide 7: Distribution of 186Re-nanoliposomes After Intra-Ommaya-ventricular Administration
Distribution of 186Re-nanoliposomes After Intra-Ommaya-ventricular Administration A B A. End of Infusion (EOI) SPECT / MRI B. 24-hour SPECT / MRI C1. AP whole body planar image at 24 hours C2. PA whole body planar image at 24 hours C1 C2 7
Slide 8: 186RNL / 188RNL: Lipid nanoparticle-carried Re radiation sources
186RNL / 188RNL: Lipid nanoparticle (nanoliposome)-carried 186Re / 188Re radiation sources M-BMEDA M = 99mTc / 186Re / 188Re 100-nm Diameter spherical shape 1. Bao A, et al. J Nucl Med 2003;44:1992–1999 biodegradable lipid nanoliposomes 2. Bao A, et al. J Pharm Sci 2003;92:1893–1904 carrying therape
Slide 9: Dose-Voxel Kernel
Dose-Voxel Kernel + Five beta-emission therapeutic radionuclides, 177Lu, 131I, 186Re, 188Re, and 90Y, with different beta- radiation energies were studied. + The dose-voxel kernels with 0.2 mm voxel size were from the data published by Graves SA, et al. + The dose – voxel kernels from origin of radi
Slide 10: Physics of Radionuclides
Physics of Radionuclides Half Life (hr) Lu-177 159.53 147.9 112.9 (6.4%); 208.4 (11.0%) 3.14 I-131 192.50 191.8 364.5 (81.7%) 4.05 Re-186 89.24 336.2 137.2 (9.42%) 7.11 Re-188 17.00 779.3 155.0 (15.6%) 16.52 Y-90 64.10 933.1 19.85 10
Slide 11: Spinal Fluid – Spinal Cord MR Segmentation
Spinal Fluid – Spinal Cord MR Segmentation The volumes of spinal cord and spinal fluid at C-spine region were segmented from T2-weighted MR image of a LM patient we treated using MIM software. + Firstly, the MR image was re-sampled to 0.2 x 0.2 x 0.2 mm3 voxel size. + The volumes of spinal fluid was
Slide 12: Radiation Absorbed Dose Calculation and Evaluation
Radiation Absorbed Dose Calculation and Evaluation The radiation absorbed dose calculation was based on that the radioactivity distributes in the leptomeningeal and spinal fluids uniformly. Brain tissue and spinal cord have no radioactivity distribution. The radiation absorbed dose calculation used
Slide 13: Dose Distribution and Dose Profile
Dose Distribution and Dose Profile 13
Slide 14: Dose Distribution Statistics
Dose Distribution Statistics Mean Dose 80% 60% 40% 20% 0% 0 0.2 0.4 0.6 0.8 1 14
Slide 15: Dose Volume Histogram (DVH) in Spinal Fluid and Spinal Cord
Dose Volume Histogram (DVH) in Spinal Fluid and Spinal Cord + Thick lines: DVH in spinal fluid; Thin lines: DVH in spinal cord. + The doses were scaled to the same mean dose in spinal fluid. 15
Slide 16: Dose Volume Histogram (DVH) in Spinal Fluid and Spinal Cord
Dose Volume Histogram (DVH) in Spinal Fluid and Spinal Cord 16
Slide 17: Summary
Summary Summary + The higher beta-energies give higher radiation absorbed doses to spinal cord. + The high beta-energy, such as Re-188 and Y-90, also results in more heterogeneous radiation absorbed dose to spinal fluid. + To maximize the radiation absorbed dose to treat LM metastasis, it is suggest
Slide 18: Discussion
Discussion Discussion + This study did not include the chemistry, pharmacokinetics, and the drug distribution throughout the entire subarachnoid space and spinal fluid. + This presentation only reports the radiation absorbed dose to spinal cord at C-spine. The overall conclusion may be applied to mo
Slide 19: Thank You!
Thank You! CANCER PREVENTION & RESEARCH INSTITUTE OF TEXAS =f THERAPEUTICS UT Health & pM CASE Y San Antonio Uni it WESTERN aan niversity Heath Scenes —=«(liversity RESERVE N Northwestern UTSouthwestern Medicine Medical Center
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