Deliberations were set to begin Friday in a case that pits pharmaceutical giant Wyeth against an Arkansas woman who claims their menopause drug was responsible for her breast cancer.

Mary Daniel’s lawsuit is the third of about 4,500 against Wyeth to reach a jury. She said that after taking Prempro — a combination of estrogen and progestin — for about 16 months to relieve hot flashes, she was diagnosed with breast cancer.