RhDNase

The advent of genetic engineering and improvements in chromatographic methodology facilitated the production of highly purified recombinant human DNase (rhDNase) preparations. Initial in vitro studies proved encouraging incubation of the enzyme with sputum derived from a cystic... 

Conway, S. and Watson, A. 1997. Nebulized bronchodilators, corticosteroids and rhDNase in adult patients with cystic fibrosis. Thorax 52(2), S64-S68. 

Menzin J, G. Oster, L. Davies, M. F. Drummond, W. Greiner, C. Lucioni, J. L. Merot, F. Rossi, V. D. Schulenberg, andE. Souetre. 1996. A Multinational Economic Evaluation of rhDNase in the Treatment of Cystic Fibrosis. International Journal of Technology Assessment in Health Care 12(1) 52-61. 

DNAse, dornase alfa, human recombinant deosyribonucelase I (rhDNAse), produced in CHO cells... 

Protein-based drugs have been formulated mainly as stable liquids or in cases where liquid stability is limiting as lyophilized dosage forms to be reconstituted with a suitable diluent prior to injection. This is because their delivery has been limited primarily to the parenteral routes of intravenous (IV), subcutaneous (SC), or intramuscular (IM) administration. There are a few drugs that have been developed for pulmonary delivery, such as rhDNase (Pulmozyme ) and an inhalable formulation of insulin (e.g., Exubra ). However, even such drugs have been formulated as either liquid or lyophilized or spray-dried powders. This chapter will focus only on excipients that are applicable to liquid and lyophilized protein formulations. 

Two examples where metal ions confer stability or increased activity in proteins are human deoxyribonuclease (rhDNase, Pulmozyme ), and Factor VIII. In the case of rhDNase, Ca2+ ions (up to 100 mM) increased the stability of the enzyme through a specific binding site (64). In fact, the removal of calcium ions from the solution with EGTA caused an increase in deamidation and aggregation. However, this effect was observed only with Ca+2 ions other divalent cations, Mg2+, Mn2+, and Zn2+, were observed to destabilize rhDNase. Similar effects were observed in Factor VIII. Ca2+ and Sr2+ ions stabilized the protein, whereas others such as Mg2+, Mn2+ and Zn2+, Cu2+, and Fe2+ destabilized the enzyme (65). In a separate study with Factor VIII, a significant increase in the aggregation rate was observed in the presence of Al3+ ions (66). The authors note that other excipients like buffer salts are often contaminated with Al3+ ions and illustrate the need to use excipients of appropriate quality in formulated products. 

PULMOZYME (Dornase Genentech alfa) [(CHO-expressed recombinant glycoprotein-human deoxyribonuclease I (rhDNase)]... 

Suri R, Grieve R, Normand C, et al. Effects of hypertonic saline, alternate day and daily rhDNase on healthcare use, costs and outcomes in children with cystic fibrosis. Thorax. 2002 57 841-846. 

Clark, A. R., Dasovich, N., Gonda, I., and Chan, H. K. The balance between biochemical and physical stability for inhalation protein powders rhDNAse as an example, in Proceedings of Respiratory Drug Delivery V. Buffalo Grove, IL Interpharm Press, 1996. 

Maa et al. [3.84] used spray drying and spray freeze-drying (see Chapter 5, [5.13, 5.14]) to produce protein powders for inhalation from deoxyribonuclease (rhDNase) and anti-IgE monoclonal antibody (anti-IgE Mab) with lactose as carrier. Spray freezedrying produced light and porous protein particles with superior aerosol performance. 

Green, J.D. 1994. Pharmaco-toxicological expert report Pulmozyme rhDNase Genentech, Inc. Hum. Exp. Toxicol. 13 Suppl 1 S1—S42. 

There is no cure for SLE. Guillermo el al. (G16) found only 10 randomized controlled trials during the past 5 years, 5 for lupus nephritis and 5 for all SLE patients. Compared to conventional therapies for lupus nephritis, a monthly bolus with intravenous cyclophosphamide is more effective than a monthly bolus with methyl prednisolone, but has significant side effects (including amenorrhea, cervical dysplasia, avascular necrosis, and herpes zoster) in both groups (G14). In order to avoid these side effects, more recent therapies have been developed. However, neither plasmapheresis (Wl), intravenous immunoglobulin (B21), recombinant human DNase (rhDNase) (D3), nor mycophenolate mofetil (C14) was shown to be more effective than conventional therapy. However, some of these... 

D3. Davis, J. C. J., Manzi, S., Yarboro, C., Rairie, J., Mcinnes, I., etal., Recombinant human DNase I (rhDNase) in patients with lupus nephritis. Lupus 8, 68—76 (1999). 

Alter short-term therapy (some weeks), in CF patients with mild to moderate stable pulmonary disease, inhalation of rhDNase in combination with other CF therapies (eg., bronchodilators, pancreatic enzymes, chest physiotherapy) improves the lung function [64.70-72], The rhDNase therapy is also associated with significant improvements in general well-being, cough frequency, and congestion [71,72],... 

According to clinical studies with rhDNase on CF patients with severe pulmonary disease, the improvement in lung function did not differ significantly from the placebo effect after 2.5 mg daily administration for 14 days [69,76], In 1994, Bryson et al. pointed out the need for longer-term studies iu order to establish the efficacy of rhDNase treatment in CF patients with severe pulmonary diseases [45]. ft has been reported that rhDNase therapy is well tolerated in CF patients with acute exacerbations urgent hospitalization [77,78]. How-... 

Besides the use of bovine pancreatic DNase I and rhDNase for the treatment of CF, the enzyme was also investigated for the treatment of other respiratory... 

Dornase alpha Recombinant enzyme Pulmozyme (rhDNAse)... 

Diot, R, Vecellio-None, L., Varaigne, F., Marchand, S., and Lemarie, E. (2003), Role of rhDNase in cystic fibrosis, Rev. Mai. Respir., 20, S171-S175. 

Geller, D., Thipphawong, J., Otulana, B., et al. (2003), Bolus inhalation of rhDNase with the AERx system in subjects with cystic fibrosis,/. Aerosol Med., 16,175-182. 

Green, J.D. Pharmacological-toxicological (expert report on recombinant human deoxyribonuclease I (rhDNase pulmo-zyme ). Human Experimental Toxicology 1994, 13, S1-S42. 

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