To assess the relative bioavailability of two different batches of Frademicina® drug product, containing 500 mg lincomycin hydrocloride, manufactured by Pfizer Laboratories Ltd. The formulations' comparative bioavailability after oral administration will be assessed based on the statistical comparisons of the relevant pharmacokinetic parameters, obtained from the drug concentrations in the blood. The lincomycin hydrocloride concentration will be measured by a proper and validated analytical method.

Inclusion Criteria:

• Men.
• Women who are not pregnant nor nursing.
• Age between 18 and 50 years-old.
• Body mass index ≥ 19 and ≤ 28,5.
• Good health conditions or with no significant diseases, under judgement of the legally qualified professional, according to the rules defined in the Protocol, and based on the following assessments: clinical history, pressure and pulse measurements, physical and psychological examination, ECG and complementary laboratorial tests.
• Ability to understand the nature and the objective of the trial, including the risks and adverse effects and, agreeing to cooperate with the investigator and to act according to the requirements of the whole assay, which will be confirmed through the signature of the Free Informed Consent.

Exclusion Criteria:

• Known hypersensitivity to the study drug (lincomycin hydrocloride) or to compounds chemically related.
• History or presence of hepatic, gastrointestinal diseases or other conditions that may interfere with the absorption, distribution, excretion or metabolism process of the drug.
• History of hepatic, renal, pulmonary, gastrointestinal, epileptic, hematological or psychiatric condition; of hypo or hypertension from any etiology that require pharmacological treatment; history or had myocardial infarction, angina and/or cardiac insufficiency.
• Electrocardiographic findings non-recommended for the enrollment in the trial, by investigator's criteria.
• Results of the laboratory tests are out of the normal range, according to the standards of this protocol, unless they are considered clinically irrelevant by the investigator.
• He/She is a smoker.
• Drinks more than 05 cups of coffee or tea per day.
• History of alcohol or drug abuse.
• Use of regular medication within 02 weeks prior to the beginning of the treatment and to the assessment date; or use of any medication within a week, except for contraceptive medications.
• Hospitalization for any reason within 08 weeks prior to the beginning of the first treatment period of this trial and to the assessment date.
• Treatment within 03 months prior to the trial with any drug with known toxic potential on primary organs.
• Enrollment to any experimental trial or use of any experimental drug within 06 months prior to the beginning of this trial and to the assessment date.
• Donation or loss of 450 mL or more of blood within 03 months that precede the trial or donation higher than 1500 mL within the 12 months between the beginning of the clinical trial and the assessment date.
• Consumption of inducing and/or inhibiting enzymatic drugs (CYP450 - hepatic), toxic to organ or with long half-life period, within 04 weeks prior to the beginning of the trial.
• Consumption of alcohol within 48 hours preceding the enrollment to the trial and during the clinical trial.
• Consumption of food and beverages that contained grapefruit up to 07 days prior to each trial period.