Inclusion Criteria:  In order to be eligible to participate in this study, a subject must meet all of the following criteria, either at the screening and Day 1 visits or only at one of the specified visits (screening or Day 1) as noted in the criterion:  Male or female subject aged 18 to 70 years, inclusive, at the time of consent. Subject has a history of plaque psoriasis for at least 6 months prior to the screening visit. Subject had no significant flare in psoriasis for at least 3 months before screening (information obtained from medical chart or subject's physician, or directly from the subject). Subject has moderate to severe plaque psoriasis as defined by a PASI score ≥ 12 and a PGA score ≥ 3 at screening and Day 1. Subject has plaque psoriasis covering ≥ 10% of his or her total BSA at screening and Day 1. Subject must be a candidate for phototherapy or systemic therapy. For female subjects of childbearing potential involved in any sexual intercourse that could lead to pregnancy: the subject must agree to use a highly effective contraceptive method from at least 4 weeks prior to Day 1 until at least 4 weeks after the last study product administration. Highly effective contraceptive methods include hormonal contraceptives (eg, combined oral contraceptive, patch, vaginal ring, injectable, or implant), intrauterine devices or intrauterine systems, vasectomized partner(s) (provided vasectomy was performed ≥ 4 months prior to screening), bilateral tubal ligation or occlusion, or double barrier methods of contraception (eg, male condom with cervical cap, male condom with diaphragm, and male condom with contraceptive sponge) in conjunction with spermicide. Female subjects of childbearing potential have had a negative serum pregnancy test at screening and negative urine pregnancy test at Day 1. For male subjects involved in any sexual intercourse that could lead to pregnancy, subject must agree to use one of the highly effective contraceptive methods listed in Inclusion Criterion 6, from Day 1 until at least 12 weeks after the last study product administration. If the female partner of a male subject uses any of the hormonal contraceptive methods listed above, this contraceptive method should be used by the female partner from at least 4 weeks before Day 1 until at least 12 weeks after the last study product administration. Subject has a BMI within the range of 18 to 38 kg/m2, inclusive (BMI = weight [kg]/[height (m)]2), and total body weight >50 kg (110 lb). Subject is willing to participate and is capable of giving informed consent. Note: Consent must be obtained prior to any study-related procedures. Subjects must be willing to comply with all study procedures and must be available for the duration of the study.  Exclusion Criteria:  A subject who meets any of the following criteria at the screening and/or Day 1 visits, as applicable, will be excluded from participation in this study:  Subject is a female who is breastfeeding, pregnant, or who is planning to become pregnant during the study. Subject has evidence of erythrodermic, pustular, predominantly guttate psoriasis, or drug induced psoriasis. Subject has a history of skin disease or presence of skin condition that, in the opinion of the investigator, would interfere with the study assessments. Subject has immune-mediated conditions commonly associated with psoriasis, such as psoriatic arthritis, uveitis, inflammatory bowel disease, that require systemic treatment (including corticosteroids, immunosuppressants, or biologics). Note: Subjects with immune-mediated conditions that do not require systemic treatment may be included in the study. Certain therapies such as NSAIDs may be permitted, but should be discussed with the Medical Monitor prior to determination of subject eligibility. Subject has any clinically significant medical condition, evidence of an unstable clinical condition (eg, cardiovascular, renal, hepatic, hematologic, gastrointestinal, endocrine, pulmonary, immunologic, or local active infection/infectious illness), psychiatric condition, or vital signs/physical/laboratory/ECG abnormality that would, in the opinion of the investigator, put the subject at undue risk or interfere with interpretation of study results. Subject had a major surgery within 8 weeks prior to Day 1 or has a major surgery planned during the study. Subject has a history of Class III or IV congestive heart failure as defined by New York Heart Association Criteria. Subject has been hospitalized in the past 3 months for asthma, has ever required intubation for treatment of asthma, currently require oral corticosteroids for the treatment of asthma, or has required more than one short-term (≤ 2 weeks) course of oral corticosteroids for asthma within 6 months prior to Day 1. Subject has a history of cancer or lymphoproliferative disease within 5 years prior to Day 1. Subjects with successfully treated non-metastatic cutaneous squamous cell or basal cell carcinoma and/or localized carcinoma in situ of the cervix are not to be excluded. Subject has a history of fever, inflammation, or systemic signs of illness suggestive of systemic or invasive infection within 4 weeks prior to Day 1. Subject has an active bacterial, viral, fungal, mycobacterial infection, or other infection (including TB or atypical mycobacterial disease), or any major episode of infection that required hospitalization or treatment with intravenous antibiotics within 12 weeks prior to Day 1, or oral antibiotics within 4 weeks prior to Day 1. Subject has a history of chronic or recurrent infectious disease, including but not limited to chronic renal infection, chronic chest infection, recurrent urinary tract infection, fungal infection (with the exception of superficial fungal infection of the nailbed), or infected skin wounds or ulcers. Subject has a history of an infected joint prosthesis or has received antibiotics for a suspected infection of a joint prosthesis, if that prosthesis has not been removed or replaced. Subject has active herpes infection, including herpes simplex 1 and 2 and herpes zoster (demonstrated on physical examination and/or medical history) within 8 weeks prior to Day 1. Subject has a history of known or suspected congenital or acquired immunodeficiency state or condition that would compromise the subject's immune status in the opinion of the investigator (eg, history of splenectomy, primary immunodeficiency). Subject has positive results for hepatitis B surface antigens (HBsAg), antibodies to hepatitis B core antigens (anti-HBc), hepatitis C virus (HCV), or human immunodeficiency virus (HIV). Subject has clinical or laboratory evidence of active or latent TB infection at screening.  Subject with any of the following laboratory values at the screening visit:  Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) values ≥ 3 times the upper limit of normal (ULN); Hemoglobin < 11.0 g/dL (< 110.0 g/L); White blood cell count < 3.5 x 109/L (< 3500/mm3); Absolute neutrophil count of < 1.8 x 109/L (< 1800/mm3); Absolute lymphocyte count of < 1.0 x 109/L (< 1000/mm3); Platelet count < 100 x 109/L (< 100,000/mm3); Total bilirubin ˃ 2 times the ULN. Subjects who have given > 50 ml of blood or plasma within 30 days of screening or > 500 mL of blood or plasma within 56 days of screening (during a clinical study or at a blood bank donation). Subject has used any topical medication that could affect psoriasis (including corticosteroids, retinoids, vitamin D analogues [such as calcipotriol], JAK inhibitors, or tar) within 2 weeks prior to Day 1. Subject has used any systemic treatment that could affect psoriasis (including oral, intravenous, intramuscular, or intralesional corticosteroids, oral retinoids, immunosuppressive/immunomodulating medication, methotrexate, cyclosporine, oral JAK inhibitors, or apremilast) within 4 weeks prior to Day 1. Subject has received any UV-B phototherapy (including tanning beds) or excimer laser within 4 weeks prior to Day 1. Subject has had PUVA treatment within 4 weeks prior to Day 1. Subject has received any live-attenuated vaccine within 4 weeks prior to Day 1 or plans to receive a live-attenuated vaccine during the study and up to 4 weeks or 5 half lives of the study product, whichever is longer, after the last study product administration. Note: Nonlive-attenuated vaccines for Coronavirus Disease 2019 (COVID-19) (eg, RNA-based vaccines, inactivated adenovirus-based vaccines, protein-based vaccines) are allowed during the study. The study site should follow local guidelines related to COVID-19. Subject is currently receiving a nonbiological investigational product or device or has received one within 4 weeks prior to Day 1. Subject has received any marketed or investigational biological agent within 12 weeks or 5 half-lives (whichever is longer) prior to Day 1 (except those listed in Exclusion Criterion 27 and 28 that are to be excluded for 6 months). Subject was previously enrolled in any study with NDI-034858. Subject has a history of lack of response to any therapeutic agent targeting IL-12, IL-17, and/or IL 23 (eg, ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab, tildrakizumab, risankizumab) at approved doses after at least 12 weeks of therapy, and/or received one of these therapies within 6 months prior to Day 1. Subject has received rituximab or other immune-cell depleting therapy within 6 months. Subject is currently being treated with strong or moderate cytochrome P450 3A (CYP3A4) inhibitors (such as itraconazole), or has received moderate or strong CYP3A4 inhibitors within 4 weeks prior to Day 1. Subject is currently being treated with terbinafine, or has received terbinafine within 4 weeks prior to Day 1. Subject has consumed grapefruit within 1 week prior to Day 1. Subject has used tanning booths within 4 weeks prior to Day 1, has had excessive sun exposure, or is not willing to minimize natural and artificial sunlight exposure during the study. Subject has a known or suspected allergy to NDI-034858 or any component of the investigational product, or any other significant drug allergy (such as anaphylaxis or hepatotoxicity). Subject has a known history of clinically significant drug or alcohol abuse in the last year prior to Day 1.  For subjects consenting to biopsy collection only:  Subject has a history of an allergic reaction or significant sensitivity to lidocaine or other local anesthetics. Subject has a history of hypertrophic scarring or keloid formation in scars or suture sites. Subject has taken anticoagulant medication, such as heparin, low molecular weight (LMW)-heparin, warfarin, or antiplatelet agents (except low-dose aspirin ≤ 81 mg which will be allowed), within 2 weeks prior to Day 1, or has a contraindication to skin biopsies. Nonsteroidal anti-inflammatory drugs will not be considered antiplatelet agents and will be allowed.