Pharmaceutical containers including sealing assembly with filler material

A method of sealing a pharmaceutical container, the method comprising:

• providing a pharmaceutical container comprising a shoulder, a neck extending from the shoulder and a flange extending from the neck, the flange comprising:
• an underside surface extending from the neck;
• an outer surface extending from the underside surface, the outer surface defining an outer diameter of the flange;
• and
• an upper sealing surface extending between the outer surface to an inner surface of the pharmaceutical container that defines an opening;
• inserting a pharmaceutical composition into the pharmaceutical container;
• and
• providing a stopper including a sealing portion extending over the upper sealing surface of the flange and covering the opening, and an insertion portion extending into the opening and in contact with the inner surface of the flange, the stopper having a first CTE, a filler member encased within the stopper and having a second CTE, the second CTE being lower than the first CTE.