adiuvant

Adiuvant is a term used in medicine as a variant spelling of adjuvant. It derives from the Latin adiuvare, meaning to help or to aid. In English medical usage, an adjuvant (or adiuvant) is a substance or treatment that enhances the effect of the primary therapy or stimulates a stronger immune response to a vaccine.

In oncology, adjuvant therapy refers to additional treatment given after the primary intervention—most commonly surgery—to reduce the risk of cancer recurrence or metastasis. Adjuvant regimens may include chemotherapy, radiotherapy, hormonal therapy, targeted therapy, or immunotherapy, and decisions depend on tumor type, stage, and patient factors.

In vaccinology, vaccine adjuvants are substances added to vaccines to improve the immune response. They can help achieve adequate antibody levels with lower vaccine doses or shorter schedules. Common adjuvants include aluminum salts; newer adjuvants such as oil-in-water emulsions, toll-like receptor agonists, and other immunostimulants are used in select formulations.

Distinguishing terms: adjuvant contrasts with neoadjuvant, which is given before the main treatment, and with palliative care, which aims to relieve symptoms without curing disease. In Latin, adiuvant is the third-person plural present indicative of adiuvare, meaning “they help.” As an English term, adjuvant is far more common, and adiuvant is mainly encountered as a historical or variant spelling.