Advancements in the Design and Development of Dry Powder Inhalers and Potential Implications for Generic Development

Dry powder inhalers (DPIs) are drug-device combination products where the complexity of the formulation, its interaction with the device, and input from users play important roles in the drug delivery. As the landscape of DPI products advances with new powder formulations and novel device designs, understanding how these advancements impact performance can aid in developing generics that are therapeutically equivalent to the reference listed drug (RLD) products. This review details the current understanding of the formulation and device related principles driving DPI performance, past and present research efforts to characterize these performance factors, and the implications that advances in formulation and device design may present for evaluating bioequivalence (BE) for generic development.

Maternal and fetal outcomes in pregnancies complicated by the inherited aortopathy Loeys-Dietz syndrome

OBJECTIVE

Pregnancies in women with Loeys-Dietz syndrome (LDS) are rare and are typically documented in case reports only. Early reports suggested high rates of maternal complications during pregnancy and the puerperium, including aortic dissection and uterine rupture, but information on fetal outcomes was very limited.

DESIGN

A retrospective cohort study.

SETTING

Eight specialist UK centres.

SAMPLE

Pregnant women with LDS.

METHODS

Data was collated on cardiac, obstetric, and neonatal outcomes.

MAIN OUTCOME MEASURES

Maternal and perinatal outcomes in pregnancies complicated by LDS.

RESULTS

Twenty pregnancies in 13 women with LDS were identified. There was one miscarriage, one termination of pregnancy, and 18 livebirths. In eight women the diagnosis was known prior to pregnancy but only one woman had preconception counselling. In four women the diagnosis was made during pregnancy through positive genotyping, and the other was diagnosed following delivery. Five women had a family history of aortic dissection. There were no aortic dissections in our cohort during pregnancy or postpartum. Obstetric complications were common, including postpartum haemorrhage (33%) and preterm delivery (50%). In all, 14/18 (78%) of deliveries were by elective caesarean section, at a median gestational age at delivery of 37 weeks. Over half the infants (56%) were admitted to the neonatal unit following delivery.

CONCLUSION

Women with LDS require multidisciplinary specialist management throughout pregnancy. Women should be referred for preconception counselling to make informed decisions around pregnancy risk and outcomes. Early elective preterm delivery needs to be balanced against a high infant admission rate to the neonatal unit.

TWEETABLE ABSTRACT

Pregnancy outcomes in women with Loeys-Dietz syndrome.

Mechanical stretch activates type 2 cyclooxygenase via activator protein-1 transcription factor in human myometrial cells

The uterus is subject to stretch throughout pregnancy, which, in the presence of progesterone, is a potent stimulus for uterine growth. However, in the absence of progesterone or when stretch is excessive, as in multiple pregnancy, it may provoke the onset of labour. We have investigated the effect of stretch on prostaglandin synthesis in primary human uterine myocytes [non-pregnant (NP), pregnant not in labour (NL) and pregnant in labour (L)]. The cells were grown on flexible bottom culture plates and subjected to 1 or 6 h static stretch. Expression of type 2 cyclooxygenase (COX-2) mRNA was similar in samples obtained from NP and L groups and both were significantly greater than those found in the NL group. Stretch of cells from all groups resulted in increased COX-2 mRNA expression. In further studies carried out on cells taken from the NL group, 6 h of stretch resulted in increased COX-2 protein levels and, in the media, increases in prostaglandin (PG) I(2) metabolite and PGE(2) concentrations and a reduction in the concentration of PGF(2)alpha metabolites. After stretch, EMSA studies showed increased activator protein-1 (AP-1) nuclear protein DNA binding activity but not of nuclear factor kappaB. These data demonstrate that stretch of human myocytes results in increased COX-2 activity and suggest that this may occur through activation of the AP-1 system.

Protective effect of Prostane in experimental prostatic hyperplasia in rats

AIM

Prostane, a polyherbal formulation, was evaluated for its efficacy on 5alpha-reductase inhibition, alpha-adrenergic antagonistic activity and testosterone-induced prostatic hyperplasia.

METHODS

5alpha-reductase inhibition was evaluated using rat prostate homogenate as an enzyme source. Adrenergic antagonistic activity was evaluated using isolated rat vas deferens. Experimental prostatic hyperplasia was induced in rats by giving testosterone 3 mg/kg sc for 21 days.

RESULTS

Prostane dose-dependently inhibited 5alpha-reductase activity and exhibited alpha-adrenergic antagonistic activity. Treatment with Prostane at 250, 500 and 750 mg/kg body wt, po for 21 days significantly reduced the prostatic weight, the epithelial height and the stromal proliferation in experimental prostatic hypertrophy.

CONCLUSION

Prostane is effective in the treatment of experimental prostatic hypertrophy in rats and may be passed on to clinical trials on benign prostatic hypertrophy after necessary toxicological evaluations.

Antioxidant activity of phytoestrogenic isoflavones

The aim of this work was to determine the antioxidant activities of a range of phytoestrogenic isoflavones. The antioxidant activity in the aqueous phase was determined by means of the ABTS.+ total antioxidant activity assay. The results show that the order of reactivity in scavenging the radical in the aqueous phase is genistein > daidzein = genistin approximately equal to biochanin A = daidzin > formononetin approximately equal to ononin, the latter displaying no antioxidant activity. The importance of the single 4'-hydroxyl group in the reactivity of the isoflavones, as scavengers of aqueous phase radicals, as well as the 5'7-dihydroxy structure is demonstrated. Examination of their abilities to enhance the resistance of low density lipoproteins to oxidation supports the observation that genistein is the most potent antioxidant among this family of compound studied, both in the aqueous and in the lipophilic phases.