Compositions and methods for treating viral infections
The present disclosure provides compositions and methods useful for treating viral infections. As described herein, the compositions and methods are based on the development of immunogenic compositions that include an attenuated or inactivated virus in combination with a non-ionic surfactant vesicle (NISV).
1. A method of increasing thermostability of an immunogenic composition, the method comprising:
melting lipids comprising 1-monopalmitoyl glycerol, dicetyl phosphate and cholesterol to produce molten lipids;
combining the molten lipids with an aqueous solution comprising an attenuated virus, wherein said attenuated virus comprises an attenuated measles virus, an attenuated mumps virus, an attenuated rubella virus, an attenuated varicella virus, or a combination thereof;
homogenizing the resulting product to produce a homogenate comprising vesicles, wherein the molten lipids and aqueous solution are combined in relative amounts and volumes that achieve a lipid concentration of about 12.5 mg/ml to about 25 mg/ml in the homogenate;
and lyophilizing the homogenate to produce an immunogenic composition, thereby increasing the level of thermostability of the immunogenic composition, relative to a comparator composition having a lipid concentration of less than about 12.5 mg/ml to about 25 mg/ml, following storage of both the immunogenic composition and the comparator composition for 12 weeks at 37±2° C.
2. The method of claim 1 , wherein the molten lipids are added to the aqueous solution comprising the attenuated virus.
3. The method of claim 1 , wherein the aqueous solution comprising the attenuated virus is added to the molten lipids.
4. The method of claim 1 , wherein at least a portion of the virus is associated with the vesicles.
5. The method of claim 1 , wherein the virus is encapsulated within an aqueous core of the vesicles.
6. The method of claim 1 , wherein the thermostable immunogenic composition lacks an alum adjuvant.
7. The method of claim 1 , further comprising comparing at least one measure of thermostability of the immunogenic composition to at least one measure of thermostability of the comparator composition.
8. The method of claim 1 , wherein the immunogenic composition exhibits less than 50% loss in potency as determined by a TCID50 assay when stored for 12 weeks at 37±2° C.