A phase Ib clinical trial of PV701, a milk-derived protein extract, for the prevention and treatment of oral mucositis in patients undergoing high-dose BEAM chemotherapy.

Despite the best available agents to prevent mucositis, most patients receiving high-dose chemoradiotherapy regimens experience severe mucositis, and new therapies are needed. In this study, we evaluated the safety and tolerability of a milk-derived growth factor extract (PV701 mouthwash) intended to prevent oral mucositis (OM) after carmustine, etoposide, cytosine arabinoside, and melphalan (BEAM) chemotherapy. PV701 mouthwash (15 mL x 13.5 mg/mL) was administered 6 times a day for 12 days, from day--6 to day +5, to patients with lymphoma, who were given BEAM on day--6 to day--2, with autologous stem cells infused on day 0. Dose de-escalation of PV701 was planned if dose-limiting toxicities occurred. The severity and duration of OM, the duration of enteral/parenteral feeding, the requirement for intravenous opiates, and admission to intensive care were recorded. Outcomes were also compared with those of historical control patients. Nine patients received PV701 13.5 mg/mL. PV701 was well tolerated, and no dose-limiting toxicities were observed. Compared with 89 historical controls, the 9 PV701-treated patients had significantly less frequent grade 2 or 3 OM ( P=.0006) and had grade>or=3 OM for an estimated 5 fewer days ( P=.0003). There was a reduction in the need for enteral/parenteral feeding ( P=.012), its duration ( P=.010), and its frequency ( P=.022) and in the duration of intravenous opiates ( P=.0006). We conclude that PV701 mouthwash is readily administered with minimal side effects at a dose of 1215 mg/d, and further investigation of this agent is warranted.

Age- and hypertension-induced changes in abnormal contractions in rat aorta.

The current investigation explored the potential age-dependant modulation of abnormal spontaneous constrictions (thromboxane-like) in the spontaneously hypertensive rat (SHR) aorta, observed only after the inhibition of endogenous production of nitric oxide (NO). Aortic rings from SHR and Wistar-Kyoto (WKY) control rats of varying ages (4, 8, 12, and 18 months) were mounted in organ baths, and changes in tension were monitored. Inhibition of NO with Nomega-nitro-L-arginine (NOLA) unmasked a slow contraction, which appeared to be age dependent (p < 0.05). This contraction was found in SHRs of all age groups and in older WKY rats. Denuding the endothelium in young SHRs did not influence the constriction, confirming a nonendothelial cell origin, while in the older groups this led to a 30-40% reduction in contraction. Comparable attenuation of the constrictor response was observed after incubation of endothelium intact rings with superoxide dismutase (100 U/ml) or 3-amino-1,2,4-triazole. Of the residual activity that was unaffected by free radical scavengers or de-endothelialization, 60-70% was sensitive to cyclooxygenase inhibition by indomethacin and/or ibuprofen. The thromboxane (TxA ) receptor antagonist SQ29548 induced a complete reversal of the abnormal constriction. In contrast, thromboxane synthetase inhibition had no effect, ruling out any involvement of TxA in mediating this abnormality. Collectively, these observations support the view that as compared with the normotensive setting, contraction induced by NO inhibition in the SHR develops prematurely and deteriorates more rapidly during the aging process. In aged rats, prostaglandin endoperoxide intermediates PGG /H and endothelium-derived free radicals rather than TxA per se appear to contribute to the NOLA-dependent TxA -like vasoconstriction.