A Study to Investigate Lithium Brain/Plasma Pharmacokinetics and Safety of an AL001 Oral Capsule Compared to a Marketed Immediate-release Lithium Carbonate Capsule in Subjects With Bipolar I Disorder

Inclusion Criteria: 1. Subjects with a primary psychiatric diagnosis of Bipolar I Disorder (BD1) between the age of ≥ 18 and ≤65 years who are in reasonably good physical health, as determined by the DSM-5-TR BD1 diagnostic criteria and the Investigator's review of medical and surgical history, physical examination (including neurological examination), 12-lead ECG, vital signs, and clinical laboratory tests. 2. Assessment of subject's mental health status will be conducted to avoid enrolling subjects who are on the verge of a manic or depressive episode. Affective stability, defined by a Young Mania Rating Scale (YMRS) rating of ≤ 11 and a Hamilton Depression Rating Scale (HDRS-17) rating of \< 16 at the Screening visit and on Day -1 (P1). Subsyndromal depression has not significantly worsened in the 4 weeks prior to randomization on Day -1 (P1) so as to avoid enrolling subjects who are on the verge of a full depressive episode. Assessment of subject's suicidal ideation and behavior (SI/B) using the Columbia-Suicide Severity Rating Scale (C-SSRS) will be conducted to avoid enrolling subjects with concerning results, defined as a history of a suicide attempt in the past two years, past year level 4 or higher suicidal ideation on the C-SSRS, or past month suicidal ideation of any kind. The "Lifetime/Recent" version will be used at screening and the "Since Last Visit" version will be used subsequently. 3. Clinically acceptable, stably dosed mood stabilizing medication regimen, including treatment regimens with atypical antipsychotic drugs, for \> 30 days prior to Screening visit, with no medication changes planned over the entire study period. See Section 6.3 for a list of medications not allowed for mood stabilization purposes. Exceptions to this may be made on a case-by-case basis following agreement by the Investigator and the Sponsor. Also, subjects with untreated BD1 can be enrolled if deemed adequately stable by the Investigator. 4. Able to understand and follow instructions during the study as determined by the Investigator. 5. Willing to follow study procedures. 6. Willing and able to adhere to study restrictions and to be confined at the clinical research center per protocol requirements. 7. Any gender, race, or ethnicity. 8. Able to understand and provide written informed consent. 9. Males (non-vasectomized and vasectomized) must agree to use barrier contraception during the study until after Treatment Period 2 in-clinic follow-up visit on Day 23 (P2). 10. Females must meet one of the following criteria: Is of childbearing potential and agrees to use an acceptable contraceptive method. Acceptable contraceptive methods include: 1. Abstinence from heterosexual intercourse from the Screening visit through to at least 30 days after the last dose of the study drug on Day 14 (P2). 2. One of the following highly-effective contraceptive methods, used from at least 28 days prior to the Screening visit through to at least 30 days after the last dose of the study drug on Day 14 (P2). * i. Systemic contraceptives (combined birth control pills, injectable/implant/insertable hormonal birth control products, or transdermal patch). * ii. Intrauterine device (with or without hormones) * iii. Male partner vasectomized at least 6 months prior to the Screening visit. 3. One of the following double-barrier contraceptive methods, used from the Screening visit through to at least 30 days after the last dose of the second study drug on Day 14 (P2): * i. Male condom used simultaneously with diaphragm plus spermicide. * ii. Male condom used simultaneously with cervical cap plus spermicide. Or Is of non-childbearing potential, defined as surgically sterile (i.e., has undergone complete hysterectomy, bilateral oophorectomy, or tubal ligation), or is in a postmenopausal state (i.e., at least 1 year without menses prior to the Screening visit). 11. Able to communicate in English, including speaking, reading, and writing. 12. Body mass index (BMI) within 18.0 to 32.0 kg/m2, inclusive, and body weight of at least 50 kg at the time of Screening. Exceptions to this can be made on a case-by-case basis following agreement by the Investigator and the Sponsor. 13. ECG recording, after at least 5 minutes of rest in a supine position, without clinically significant abnormalities as determined by the Investigator. Exclusion Criteria: 1. Clinically significant abnormalities detected by medical history, physical examination, vital sign measurements, ECG findings (including prolonged QT interval), or clinical laboratory findings (as determined by the Investigator) that may affect the safety or successful participation of the subject. Specifically, evidence of clinically significant hematological, renal, endocrine, pulmonary, cardiovascular, dermatologic, muscular, or allergic disease or disorder (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at time of dosing) that may affect the safety or successful participation of the subject. 2. Well defined diagnosis of drug sensitives with moderate to severe reactions (i.e., full body urticaria, reactions requiring hospitalization, etc.). 3. Presence or history of any disorder other than the diagnosis under study that may prevent the successful completion of the study. 4. Other severe acute, chronic, or historical medical or psychiatric condition or laboratory abnormality or social circumstance that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the Investigator, would make the subject inappropriate for entry into this study. 5. History of seizure disorder and/or severe head trauma (other than a single childhood febrile seizure). 6. Current uncontrolled gastrointestinal disease of moderate to severe nature such as chronic gastritis, peptic ulcers, i