Intratumoral Injection of Large Surface Area Microparticle Taxanes in Carcinomas Increases Immune Effector Cell Concentrations, Checkpoint Expression, and Synergy with Checkpoint Inhibitors: A Review of Preclinical and Clinical Studies.

This review summarizes development of large surface area microparticle paclitaxel (LSAM-PTX) and docetaxel (LSAM-DTX) for local treatment of primary carcinomas with emphasis on immunomodulation. Intratumoral (IT) delivery of LSAM-PTX and LSAM-DTX provides continuous, therapeutic drug levels for several weeks. Preclinical studies and clinical trials reported a reduction in tumor volume (TV) and immunomodulation in primary tumor and peripheral blood with increases in innate and adaptive immune cells and decreases in suppressor cells. Increased levels of checkpoint expression of immune cells occurred in clinical trials of high-risk non-muscle-invasive bladder cancer (LSAM-DTX) and unresectable localized pancreatic cancer (LSAM-PTX). TV reduction and increases in immune effector cells occurred following IT LSAM-DTX and IT LSAM-PTX together with anti-mCTLA-4 and anti-mPD-1, respectively. Synergistic benefits from combinatorial therapy in a 4T1-Luc breast cancer model included reduction of metastasis with IT LSAM-DTX + anti-mCTLA-4. IT LSAM-PTX and LSAM-DTX are tumoricidal, immune enhancing, and may improve solid tumor response to immune checkpoint inhibitors without additional systemic toxicity.

Intratumoral Treatment of Melanoma Tumors with Large Surface Area Microparticle Paclitaxel and Synergy with Immune Checkpoint Inhibition.

The effects of intratumoral (IT) large surface area microparticle paclitaxel (LSAM-PTX) alone and in combination with systemic administration of the programmed cell death protein antibody (anti-mPD-1) were evaluated in a syngeneic murine model of melanoma. Groups of mice with subcutaneously implanted Clone M3 (Cloudman S91) tumors were treated with single and combination therapies. Tumor volume (TV) measurements, body weights, and clinical observations were followed in-life. At end of study, tumor-site tissues were collected, measured, and processed for flow cytometry along with blood and lymph nodes. The combination of LSAM-PTX + anti-mPD-1 resulted in an antitumoral response, which produced a significant decrease in TV compared to control animals. TV decreases also occurred in the LSAM-PTX and anti-mPD-1 groups. Flow cytometry analysis found increases in granulocytes and M2 macrophages and decreases in dendritic cells (DC) and monocytic myeloid-derived suppressor cells (M-MDSC) in tumor-site tissues. Increases in granulocytes and decreases in CD4+ T cells, macrophages, and M1 macrophages were found in the blood of animals administered the combination treatment. Increases in natural killer (NK) cells were found in lymph node tissue in the combination treatment group. These findings suggest that IT LSAM-PTX may provide benefit in the local treatment of melanomas and may synergize with systemic anti-PD-1 therapy, leading to additional tumoricidal outcomes without added systemic toxicity.

Phase 1/2 Trial Results of a Large Surface Area Microparticle Docetaxel for the Treatment of High-Risk Nonmuscle-Invasive Bladder Cancer.

PURPOSE: We investigated the safety, preliminary efficacy, and immune effects of large surface area microparticle docetaxel (LSAM-DTX) administered by direct injection after transurethral resection of bladder tumor (TURBT), and by intravesical instillation in high-risk nonmuscle-invasive bladder cancer. MATERIALS AND METHODS: The trial followed an open-label 3+3 dose escalation with additional enrollment at the high dose. After TURBT, subjects received direct injection LSAM-DTX into the resection site and intravesical LSAM-DTX, followed by 6-week induction and 3-week maintenance intravesical LSAM-DTX courses. Tumor recurrence was evaluated by cytology, cystoscopy, or biopsy. Pharmacokinetic analysis of blood and multiplex immunofluorescence of tumor microenvironment occurred pre- and post-LSAM-DTX. RESULTS: Nineteen subjects were enrolled, 14 with prior bacillus Calmette-Guérin exposure and 16 with ≥1 prior TURBT. Direct injection and intravesical LSAM-DTX were well tolerated. In the 3 lowest dose escalation cohorts the median recurrence-free survival was 5.4 months (10 patients, median followup 8.6 months). In the high-dose and expansion cohorts median recurrence-free survival was significantly increased (p <0.05, hazard ratio 0.29) to 12.2 months (9 patients, median followup 12.4 months). Systemic docetaxel exposure was negligible and increases in antitumor immune cells were found in the tumor microenvironment along with elevations in the PD-1, PD-L1 and CTLA-4 immune checkpoint inhibitor targets. CONCLUSIONS: Post-TURBT direct injection and intravesical LSAM-DTX were well tolerated and demonstrated clinical response for patients with high-risk nonmuscle-invasive bladder cancer. Favorable immune cell infiltration and checkpoint receptor increases following LSAM-DTX treatment warrants investigation alone as well as in combination with immune checkpoint inhibitor therapy.

Intratumoral submicron particle docetaxel inhibits syngeneic Renca renal cancer growth and increases CD4+, CD8+, and Treg levels in peripheral blood.

Administration of chemotherapeutics as direct injections into tumors offers increased anti-tumor activity and reduced systemic toxicity. In this study, the Renca syngeneic murine xenograft model of renal cancer was used to evaluate the effects of intratumoral (IT) submicron particle docetaxel (NanoDoce®) on tumor growth and immunomodulation. Tumor volume (TV) was compared to controls, including intravenous (IV) chemotherapy. Flow cytometry of peripheral bloods and tumors was used to evaluate immune cell populations. Groups of animals were inoculated with a second Renca tumor at a site distant from the primary tumor. IT NanoDoce significantly reduced primary TV and reduced the growth rates of untreated secondary tumors. CD4+, CD8+ and Treg populations were increased in peripheral bloods from animals administered IT NanoDoce. Additional evaluation of the effect of IT NanoDoce on peripheral and local immune cell populations as well as the impact on sites of distant tumor growth are warranted.

Local Injection of Submicron Particle Docetaxel is Associated with Tumor Eradication, Reduced Systemic Toxicity and an Immunologic Response in Uro-Oncologic Xenografts.

Intratumoral (IT) administration of submicron particle docetaxel (NanoDoce®, NanOlogy LLC, Fort Worth, TX, USA) and its efficacy against genitourinary-oncologic xenografts in rats and mice, xenograft-site docetaxel concentrations and immune-cell infiltration were studied. IT-NanoDoce®, IV-docetaxel and IT-vehicle were administered to clear cell renal carcinoma (786-O: rats), transitional cell bladder carcinoma (UM-UC-3: mice) and prostate carcinoma (PC-3: mice). Treatments were given every 7 days with 1, 2, or 3 doses administered. Animals were followed for tumor growth and clinical signs. At necropsy, 786-O and UM-UC-3 tumor-site tissues were evaluated by H&E and IHC and analyzed by LC-MS/MS for docetaxel concentration. Two and 3 cycles of IT-NanoDoce® significantly reduced UM-UC-3 tumor volume (p < 0.01) and eliminated most UM-UC-3 and 786-O tumors. In both models, NanoDoce® treatment was associated with (peri)tumor-infiltrating immune cells. Lymphoid structures were observed in IT-NanoDoce®-treated UM-UC-3 animals adjacent to tumor sites. IT-vehicle and IV-docetaxel exhibited limited immune-cell infiltration. In both studies, high levels of docetaxel were detected in NanoDoce®-treated animals up to 50 days post-treatment. In the PC-3 study, IT-NanoDoce® and IV-docetaxel resulted in similar tumor reduction. NanoDoce® significantly reduced tumor volume compared to IT-vehicle in all xenografts (p < 0.0001). We hypothesize that local, persistent, therapeutic levels of docetaxel from IT-NanoDoce® reduces tumor burden while increasing immune-cell infiltration. IT NanoDoce® treatment of prostate, renal and bladder cancer may result in enhanced tumoricidal effects.

Development of a guinea pig cutaneous radiation injury model using low penetrating X-rays.

PURPOSE: A guinea pig skin model was developed to determine the dose-dependent response to soft X-ray radiation into the dermis. MATERIALS AND METHODS: X-ray exposure (50 kVp) was defined to a 4.0 × 4.0 cm area on the lateral surface of a guinea pig using lead shielding. Guinea pigs were exposed to a single fraction of X-ray irradiation ranging from 25-79 Gy via an XRAD320ix Biological Irradiator with the collimator removed. Gross skin changes were measured using clinical assessments defined by the Kumar scale. Skin contracture was assessed, as well as histological evaluations. RESULTS: Loss of dermal integrity was shown after a single dose of soft X-ray radiation at or above 32 Gy with the central 2.0 × 2.0 cm of the exposed site being the most affected. Hallmarks of the skin injury included moist desquamation, ulceration and wound contracture, as well as alterations in epithelium, dermis, muscle and adipose. Changes in the skin were time- and radiation dose-dependent. Full-thickness injury occurred without animal mortality or gross changes in the underlying organs. CONCLUSIONS: The guinea pig is an appropriate small animal model for the short-term screening of countermeasures for cutaneous radiation injury (CRI).

NorLeu3-Angiotensin (1-7) [DSC127] as a Therapy for the Healing of Diabetic Foot Ulcers.

Significance: Diabetes is a disorder that is well known to delay wound repair resulting in the formation of colonized chronic wounds. Over their lifetime, diabetic patients have a 25% incidence of foot ulcers (DFUs), which contribute to increased risk of morbidity, including osteomyelitis and amputations, and increased burden to the healthcare system. Recent Advances: The only active product approved for the treatment of diabetic ulcers, Regranex®, is not widely used due to minimal proven efficacy and recent warnings added to the Instructions for Use. A novel topical agent that accelerates healing and increases the proportion of fully healed DFUs, DSC127 [aclerastide; active ingredient, NorLeu3-angiotensin (1-7) (NorLeu3-A(1-7))], is recruiting patients in Phase III clinical trials (NCT01830348 and NCT01849965). NorLeu3-A(1-7) is an analog of the naturally occurring peptide, angiotensin 1-7. The mechanisms of action include induction of progenitor proliferation, accelerated vascularization, collagen deposition, and re-epithelialization. Critical Issues: Current modalities for the treatment of DFUs include strict offloading, bandaging, debridement and, on a limited basis, application of Regranex. Novel potent therapies are needed to combat this significant burden to the diabetic patient and the healthcare system. Future Direction: Preclinical and clinical research shows that DSC127 is highly effective in the closure of diabetic wounds and is superior to Regranex in animal studies. Clinical development of DSC127 as a topical agent for the healing of DFU is underway. Further investigation into the mechanisms by which this product accelerates healing is warranted.

A phase I study of intraperitoneal nanoparticulate paclitaxel (Nanotax®) in patients with peritoneal malignancies.

PURPOSE: This multicenter, open-label, dose-escalating, phase I study evaluated the safety, tolerability, pharmacokinetics and preliminary tumor response of a nanoparticulate formulation of paclitaxel (Nanotax®) administered intraperitoneally for multiple treatment cycles in patients with solid tumors predominantly confined to the peritoneal cavity for whom no other curative systemic therapy treatment options were available. METHODS: Twenty-one patients with peritoneal malignancies received Nanotax® in a modified dose-escalation approach utilizing an accelerated titration method. All patients enrolled had previously received chemotherapeutics and undergone surgical procedures, including 33 % with optimal debulking. Six doses (50-275 mg/m(2)) of Cremophor-free Nanotax® were administered intraperitoneally for one to six cycles (every 28 days). RESULTS: Intraperitoneal (IP) administration of Nanotax® did not lead to increases in toxicity over that typically associated with intravenous (IV) paclitaxel. No patient reported ≥Grade 2 neutropenia and/or ≥Grade 3 neurologic toxicities. Grade 3 thrombocytopenia unlikely related to study medication occurred in one patient. The peritoneal concentration-time profile of paclitaxel rose during the 2 days after dosing to peritoneal fluid concentrations 450-2900 times greater than peak plasma drug concentrations and remained elevated through the entire dose cycle. Best response assessments were made in 16/21 patients: Four patients were assessed as stable or had no response and twelve patients had increasing disease. Five of 21 patients with advanced cancers survived longer than 400 days after initiation of Nanotax® IP treatment. CONCLUSIONS: Compared to IV paclitaxel administration, Cremophor-free IP administration of Nanotax® provides higher and prolonged peritoneal paclitaxel levels with minimal systemic exposure and reduced toxicity.

Effect of combined radiation injury on cell death and inflammation in skin.

In the event of a nuclear disaster, the individuals proximal to the source of radiation will be exposed to combined radiation injury. As irradiation delays cutaneous repair, the purpose of this study was to elucidate the effect of combined radiation and burn injury (CRBI) on apoptosis and inflammation at the site of skin injury. Male C57Bl/6 mice were exposed to no injury, thermal injury only, radiation only (1 and 6 Gy) and CRBI (1 and 6 Gy) and euthanized at various times after for skin collection. TUNEL staining revealed that the CRBI 6 Gy group had a delayed and increased apoptotic response. This correlated with decreased recovery of live cells as compared to the other injuries. Similar response was observed when cleaved-caspase-3 immunohistochemical staining was compared between CRBI 6 Gy and thermal injury. TNFR1, caspase 8, Bax and IL-6 mRNA expression revealed that the higher CRBI group had delayed increase in mRNA expression as compared to thermal injury alone. RIPK1 mRNA expression and necrotic cell counts were delayed in the CRBI 6 Gy group to day 5. TNF-α and NFκB expression peaked in the CRBI 6 Gy group at day 1 and was much higher than the other injuries. Also, inflammatory cell counts in the CRBI 6 Gy group were lower at early time points as compared to thermal injury by itself. These data suggest that CRBI delays and exacerbates apoptosis and inflammation in skin as well as increases necrosis thus resulting in delayed wound healing.

Reduction of Leg Pain by Oxiplex Gel After Lumbar Discectomy in Patients With Predominant Leg Pain and Elevated Levels of Lower Back Pain: A Prospective, Randomized, Blinded, Multicenter Clinical Study.

STUDY DESIGN: A prospective, randomized, blinded, multicenter clinical study. OBJECTIVE: To evaluate carboxymethylcellulose/polyethylene oxide gel (Oxiplex) in improving clinical outcomes in subjects having predominant leg pain and elevated low back pain undergoing first-time lumbar discectomy for disk herniation. SUMMARY OF BACKGROUND DATA: Clinical studies in the United States and Italy found that Oxiplex reduced leg pain after decompression surgery. METHODS: A total of 68 subjects with herniated lumbar disk were enrolled and randomized into treatment (surgery plus gel) or surgery-only control groups. A prospective statistical analysis assessed the effect of gel in the severe back pain subgroup (prespecified as greater than or equal to median baseline back pain of the population studied). All subjects except 2 controls lost to follow-up completed the study. Preoperative and postoperative visual analogue scale leg pain scores were analyzed and compared between groups at 60 days after surgery. RESULTS: There were no serious adverse events or neurological safety concerns reported in any patients. Gel-treated patients had statistically significantly lower visual analogue scale leg pain scores at study end compared with controls (P=0.0240), representing a 21% additional reduction in leg pain compared with surgery alone in the severe baseline back pain subgroup (P=0.0240). The proportion of subgroup patients experiencing zero leg pain at study end was significantly higher in the gel treatment group (60%) than in the control group (23%) (P=0.0411). CONCLUSIONS: The data from this study confirm and extend results of 2 previous studies in Italy and the United States that reported statistically significantly greater reductions in leg pain in gel-treated patients with severe preoperative low back pain compared with patients who only underwent decompression surgery.

Angiotensin 1 - 7 stimulation of platelet recovery.

INTRODUCTION: Thrombocytopenia is an abnormally low number of platelets in the blood resulting from either too few platelets being produced or existing platelets being destroyed. Severe thrombocytopenia leads to excessive bleeding and can be the result of numerous medical conditions or a side effect of medications or treatments. Although platelet transfusions are typically administered to correct thrombocytopenia, transfusions represent a temporary and unsustainable solution. As there is a limited supply of platelet units available for transfusion, along with the significant financial cost and risk of infection, investigation to uncover mechanisms that boost platelet production may have important clinical and therapeutic implications. Treatment with angiotensin 1 - 7 (A(1 - 7)) has been shown in a preclinical and clinical evaluations to have a positive effect on platelet recovery. AREAS COVERED: The authors provide an overview of the current treatment options available for platelet recovery and highlight the need for alternatives. Following on, the authors discuss the use of A(1 - 7) as a potential therapeutic option for platelet recovery, including its safety and efficacy. EXPERT OPINION: Current evidence provides a good basis for continued research and evaluation of the benefits of A(1 - 7) treatment in stimulating platelet recovery following myelosuppression. A(1 - 7) therapy has the potential to make a significant contribution to healthcare by providing standalone and additive treatments to address unmet medical needs and life-threatening diseases by utilizing the regenerative arm of the renin-angiotensin system.

Angiotensin-(1-7) synergizes with colony-stimulating factors in hematopoietic recovery.

PURPOSE: Angiotensin (1-7) [A(1-7)] is a bioactive peptide of the renin angiotensin system that stimulates the number of bone marrow progenitors and hematopoietic recovery after myelosuppression. We evaluated the combination of A(1-7) with colony-stimulating factors, Neupogen and Epogen, on bone marrow progenitors and the recovery of circulating formed elements following chemotherapy. METHODS: Mice were injected with gemcitabine followed 2 days later with A(1-7). Circulating blood cells and bone marrow progenitors were measured over time. RESULTS: Combination of A(1-7) with Neupogen (the latter given only 3 days starting at the white blood cell nadir) decreased the amount of Neupogen needed for optimal recovery by 10-fold. The progenitors measured include CFU-GEMM, CFU-GM, CFU-Meg and BFU-E. A(1-7) increased recovery of all progenitors when given alone or in combination with Neupogen above that with Neupogen alone. Combination of A(1-7) with Epogen slightly increased (not significantly) red blood cell concentrations above those achieved by Epogen alone. However, in this model, A(1-7) or A(1-7) in combination with Epogen increased all erythroid progenitors with the largest effect on early erythroid progenitors (immature BFU-E). CONCLUSIONS: Neupogen and Epogen acted synergistically with A(1-7) to increase the concentration of myeloid, megakaryocytic and erythroid progenitor cells in the bone marrow following chemotherapy suggesting that A(1-7)'s multilineage effect on early progenitors in the marrow facilitates proliferation in response to lineage-specific growth factors.

Contribution of the Local RAS to Hematopoietic Function: A Novel Therapeutic Target.

The renin-angiotensin system (RAS) has long been a known endocrine system that is involved in regulation of blood pressure and fluid balance. Over the last two decades, evidence has accrued that shows that there are local RAS that can affect cellular activity, tissue injury, and tissue regeneration. There are locally active ligand peptides, mediators, receptors, and signaling pathways of the RAS in the bone marrow (BM). This system is fundamentally involved and controls the essential steps of primitive and definitive blood-cell production. Hematopoiesis, erythropoiesis, myelopoiesis, thrombopoiesis, formation of monocytic and lymphocytic lineages, as well as stromal elements are regulated by the local BM RAS. The expression of a local BM RAS has been shown in very early, primitive embryonic hematopoiesis. Angiotensin-converting enzyme (ACE-1, CD143) is expressed on the surface of hemangioblasts and isolation of the CD143 positive cells allows for recovery of all hemangioblast activity, the first endothelial and hematopoietic cells, forming the marrow cavity in the embryo. CD143 expression also marks long-term blood-forming CD34+ BM cells. Expression of receptors of the RAS is modified in the BM with cellular maturation and by injury. Ligation of the receptors of the RAS has been shown to modify the status of the BM resulting in accelerated hematopoiesis after injury. The aim of the present review is to outline the known functions of the local BM RAS within the context of primitive and definitive hematopoiesis as well as modification of BM recovery by administration of exogenous ligands of the RAS. Targeting the actions of local RAS molecules could represent a valuable therapeutic option for the management of BM recovery after injury as well as neoplastic disorders.

Pharmacodynamic stimulation of thrombogenesis by angiotensin (1-7) in recurrent ovarian cancer patients receiving gemcitabine and platinum-based chemotherapy.

PURPOSE: This randomized, double-blind, placebo-controlled Phase 2 study evaluated safety and efficacy of A(1-7) for reduction in Grade 3-4 thrombocytopenia in patients receiving myelosuppressive chemotherapy. Pharmacodynamic activity of A(1-7) in platelet production and retention of scheduled dose intensity were also determined. METHODS: Thirty-four patients with ovarian, Fallopian tube, or peritoneal carcinoma receiving gemcitabine and carboplatin or cisplatin were evaluated. Patients were randomized to receive study drug subcutaneously at 100 mcg/kg (n = 11), 300 mcg/kg (n = 13), or placebo (n = 10) following chemotherapy for up to six cycles. Hematologic variables were obtained throughout each treatment cycle. RESULTS: There were no drug-related safety issues. There were no instances of Grade 4 thrombocytopenia in patients who received 100 mcg/kg treatment compared to 6 % of chemotherapy cycles for patients receiving placebo (p = 0.07). The maximal percentage increase in platelet concentration from baseline was higher for patients who received 100 mcg/kg A(1-7) compared to placebo (p = 0.02). This increase was accompanied by a reduction in the nadir absolute neutrophil count (p = 0.04). Relative dose intensity for the combination chemotherapy was higher for patients who received 100 mcg/kg A(1-7) compared to placebo (p = 0.04). There were no differences in outcomes for patients receiving 300 mcg/kg dose compared to placebo. CONCLUSIONS: A 100 mcg/kg dose of A(1-7) was shown to produce pharmacodynamic effects on peripheral blood platelet counts, preserve planned dose intensity, and reduce Grade 3-4 thrombocytopenia following gemcitabine and platinum chemotherapy. These findings are consistent with A(1-7)-induced stimulation of thrombogenesis in the bone marrow following marrow-toxic chemotherapy.

Effects of combined radiation and burn injury on the renin-angiotensin system.

The renin-angiotensin system (RAS) plays an important role in wound repair; however, little is known pertaining to RAS expression in response to thermal injury and the combination of radiation plus burn injury (CRBI). The purpose of this study was to test the hypothesis that thermal injury modifies expression of RAS components and CRBI delayed this up-regulation of RAS. Skin from uninjured mice was compared with mice receiving local thermal injury or CRBI (injury site). Skin was analyzed for gene and protein expression of RAS components. There was an initial increase in the expression of various components of RAS following thermal injury. However, in the higher CRBI group there is an initial decrease in AT(1b) (vasoconstriction, pro-proliferative), AT(2) (vasodilation, differentiation), and Mas (vasodilation, anti-inflammatory) gene expression. This corresponded with a delay and decrease in AT(1) , AT(2) , and MAS protein expression in fibroblasts and keratinocytes. The reduction in RAS receptor positive fibroblasts and keratinocytes correlated with a reduction in collagen deposition and keratinocyte infiltration into the wounded area resulting in a delay of reepithelialization following CRBI. These data support the hypothesis that delayed wound healing observed in subjects following radiation exposure may be in part due to decreased expression of RAS.

NorLeu3-A(1-7) stimulation of diabetic foot ulcer healing: results of a randomized, parallel-group, double-blind, placebo-controlled phase 2 clinical trial.

This randomized, double-blind, placebo-controlled Phase 2 clinical trial explored NorLeu(3)-A(1-7) (DSC127) safety and healing efficacy in diabetic foot ulcers. Patients with chronic, noninfected, neuropathic, or neuroischemic plantar Wagner Grade 1 or 2 foot ulcers (n = 172) were screened for nonhealing. Subjects were randomized to receive 4 weeks' once-daily topical treatment with 0.03% DSC127 (n = 26), 0.01% DSC127 (n = 27), or Placebo (n = 24), followed by 20 weeks' standard of care. DSC127 was assessed for safety (including laboratory values and adverse events), primary efficacy (% ulcers completely epithelialized at Week 12), and durability of effect. Baseline, demography, and safety parameters were compared between intent-to-treat groups and were comparable. Dose-response curves for DSC127 effect on % area reduction from baseline at Week 12 (40% placebo; 67% 0.01% DSC127; 80% 0.03% DSC127) and 24 (23% placebo; 53% 0.01% DSC127; 95% 0.03% DSC127) followed a log-linear pattern for both intent-to-treat and per-protocol populations. Covariate analysis compared reduction in ulcer area, depth, and volume from baseline; reductions in the 0.03% DSC127 group were greater at Weeks 12 and 24. Placebo-treated ulcers healed in a median 22 weeks vs. 8.5 weeks for 0.03%DSC127 (p = 0.04). This study provides preliminary evidence that DSC127 is safe and effective in accelerating the healing of diabetic foot ulcers.

Accelerated hematopoietic recovery with angiotensin-(1-7) after total body radiation.

PURPOSE: Angiotensin (1-7) [A(1-7)] is a component of the renin angiotensin system (RAS) that stimulates hematopoietic recovery after myelosuppression. In a Phase I/IIa clinical trial, thrombocytopenia after chemotherapy was reduced by A(1-7). In this study, the ability of A(1-7) to improve recovery after total body irradiation (TBI) is shown with specific attention to radiation-induced hematopoietic injury. MATERIALS AND METHODS: Mice were exposed to TBI (doses of 2-7 Gray [Gy]) of cesium 137 gamma rays, followed by treatment with A(1-7), typical doses were 100-1000 µg/kg given once or once daily for a specified number of days depending on the study. Animals are injected subcutaneously via the nape of the neck with 0.1 ml drug in saline. The recovery of blood and bone marrow cells was determined. Effects of TBI and A(1-7) on survival and bleeding time was also evaluated. RESULTS: Daily administration of A(1-7) after radiation exposure improved survival (from 60% to 92-97%) and reduced bleeding time at day 30 after TBI. Further, A(1-7) increased early mixed progenitors (3- to 5-fold), megakaryocyte (2- to 3-fold), myeloid (3- to 6-fold) and erythroid (2- to 5-fold) progenitors in the bone marrow and reduced radiation-induced thrombocytopenia (RIT) (up to 2-fold). Reduction in the number of treatments to 3 per week also improved bone marrow recovery and reduced RIT. As emergency responder and healthcare systems in case of nuclear accident or/and terrorist attack may be overwhelmed, the consequence of delayed initiation of treatment was ascertained. Treatment with A(1-7) can be delayed up to 5 days and still be effective in the reduction of RIT or acceleration of bone marrow recovery. CONCLUSIONS: The data presented in this paper indicate that A(1-7) reduces the consequences of critical radiation exposure and can be initiated well after initial exposure with maximal effects on early responding hematopoietic progenitors when treatment is initiated 2 days after exposure and 5 days after exposure for the later responding progenitors and reduced thrombocytopenia. There was some effect of A(1-7) even when given days after radiation exposure.

Toxicological and toxicokinetic analysis of angiotensin (1-7) in two species.

The objectives of this study were to determine the potential systemic and local toxicity, as well as evaluate the toxicokinetic (TK) profile of angiotensin (1-7) [A(1-7)] when administered daily via subcutaneous injection for 28 days to Sprague-Dawley rats and Beagle dogs. A(1-7) is a member of the renin-angiotensin system and has undergone clinical evaluation for the treatment of chemotherapy-induced myelosuppression. In this present study, A(1-7) was given at 10 mg/(kg day) for 28 days to rats and canines. At day 27, blood was harvested to evaluate the TK parameters. On day 28, systemic toxicology was evaluated. Following A(1-7) administration for 27 days, no plasma A(1-7) accumulation was detected in canines; however, increased A(1-7) plasma concentrations were detected in rats. Despite the accumulation observed in rats, no detectable toxicity was found following A(1-7) administration for 28 days. The TK analysis of A(1-7) revealed a plasma half-life of 20-30 min in both rats and canines. The time to maximum plasma concentration was found to be 15 and 26.25 min in rats and canines, respectively. This study shows that subcutaneous administration of A(1-7) at 10 mg/(kg day) for 28 days did not lead to any detectable toxicities in either rats or canines.

Oxiplex reduces leg pain, back pain, and associated symptoms after lumbar discectomy.

STUDY DESIGN: Prospective, randomized, blinded clinical trial. OBJECTIVE: To evaluate effectiveness of Oxiplex gel for reduction of pain and associated symptoms after lumbar discectomy. SUMMARY OF BACKGROUND DATA: Oxiplex gel (carboxymethylcellulose, polyethylene oxide, and calcium) is used during discectomy to coat the surgical site for reduction of pain and symptoms after lumbar discectomy. METHODS: Patients undergoing single-level lumbar discectomy performed by laminectomy or laminotomy and randomized to receive either surgery plus Oxiplex gel (treatment group) or surgery alone (control group) were assessed 6 months after surgery using (1) a quality of life questionnaire (Lumbar Spine Outcomes Questionnaire [LSOQ]) and (2) clinical evaluations. RESULTS: There were no statistically significant differences in baseline demographics, surgical procedures, LSOQ scores, and clinical evaluations between treatment (N = 177) and control (N = 175) groups. More gel-treated patients were satisfied with outcome of their surgical treatment than control patients (P = 0.05). The gel-treated group showed greater reductions in pain and symptoms from baseline compared with surgery-only controls. Additional benefits of gel were consistently shown in reduction of leg and back pain at 6 months in the patient population having substantial back pain at baseline (greater than or equal to the median LSOQ pain score of 63). In that population, there was a statistically significant reduction of leg pain and back pain (P < 0.01) in the treatment group compared with controls. Fewer patients in the treatment group had abnormal musculoskeletal physical examinations at 6 months compared with controls. There were no cases of cerebrospinal fluid leaks and no differences in laboratory values or vital signs. Patients in the treatment group had less hypoesthesia, paraesthesia, sensory loss, and fewer reoperations during the 6-month follow-up than controls (1 vs. 6). CONCLUSION: These data demonstrate improvements in clinical outcomes resulting from the use of Oxiplex gel in discectomy procedures for treatment of lumbar disc herniation.

Prevention of intra-abdominal adhesions in gynaecological surgery.

Important progress has been made in the field of post-surgical adhesion prevention with the development of consensus statements in gynaecology from the United Kingdom, Germany, the European Society of Gynaecological Endoscopy, Call for Action in Colorectal Surgery and a recent Technical Bulletin from The Practice Committee of the American Society of Reproductive Medicine. These reports suggest that the application of adhesion reduction devices together with the use of microsurgical principles reduces the formation of post-operative adhesions. This commentary provides additional information to assist gynaecologists in making surgical decisions. However, variation in adhesion classifications, mode of device application, lack of uniformity in surgical approaches and variations in interpretation of results make comparative assessment of the efficacy of adhesion reduction devices and surgical techniques difficult. Considering the choice of an adhesion-reduction device, one has to evaluate the cost and its clinical impact carefully. This is particularly important if one were to support routine, prophylactic use of adhesion-reduction devices. Healthcare providers should take into account the needs of individual patients, available resources, and institutional or clinical practice limitations. Good surgical technique and perhaps the use of approved devices for adhesion reduction would give patients the best chance to benefit from reproductive and gynaecological surgery.