Evaluating the Safety and Efficacy of PNMR as Treatment for Long COVID

Inclusion Criteria: The patient must meet all the following criteria to be enrolled in the study: 1. ≥19 years of age. 2. Negative COVID-19 test for a minimum of four (4) weeks prior to enrollment in the study. 3. Confirmed COVID-19 diagnosis by Polymerase chain reaction (PCR) test, antibody test, or clinical diagnosis more than four (4) weeks prior to enrollment in the study. 4. Long COVID diagnosis according to the WHO criteria, specifically the continuation or development of new symptoms three months after the initial SARS-COV-2 infection, with these symptoms lasting for more than two months with no other explanation. 5. For women of childbearing potential involved in any sexual intercourse that could lead to pregnancy: Negative pregnancy test and willingness to use contraceptive (consistent with local regulations) during the study period. Approved contraceptive methods include contraceptive pills or patches, hormonal implants, intrauterine device (IUD), diaphragm or cervical cap with spermicide, and condos with spermicide. Note: If participant become pregnant during the study, they must stop taking the study products immediately and inform the study investigator. 6. Patient agrees to stop taking any over the counter supplements, vitamins, or natural products as well as any of the prohibited medications during the study. 7. Patient agrees not to use medications affecting directly (or potentially) the objectives of the study such as fatigue and cognitive function during the study. 8. Willing to adhere to the study diet and exercise recommendations to the best of the patient's ability. 9. Willing to complete the 6MWT. 10. Willing to complete the patient self-administered questionnaires and diaries. 11. Signed informed consent form by any patient capable of giving consent, or, when the patient is not capable of giving consent, by his or her legal/authorized representatives. Exclusion Criteria: 1. Subject is a female who is breastfeeding or pregnant or trying to conceive. 2. Subject with a vegetarian diet or not able to follow the dietary guidelines. 3. Known hypersensitivity to PNMR or its ingredients. 4. Participating in other drug clinical trials (participation in COVID-19 antiviral trials may be permitted if approved by sponsor). 5. Any condition that in the opinion of the investigator participation in the trial increases the risk to the patient. 6. 4 weeks or more of consecutive daily supplement use of 5000 IUs Vitamin D / day and/or 50mg Zinc (without copper) / day within 4 weeks of Day 0. 7. Use of any medications or treatments for which treatment with PNMR is counter-indicated. 8. Subject is not able to swallow a larger number of capsules. 9. Any condition that in the opinion of the investigator would confound the study results or would prevent the patient to complete the study. 10. Any patient for whom vitamin D3 (cholecalciferol) is contraindicated per the following patient situations: 1. Hypersensitivity to vitamin D, any of its analogues and derivatives or to any ingredient in the formulation 2. Hypercalcemia and/or hypercalciuria 3. Nephrolithiasis (renal calculi) 4. Severe renal impairment (eGFR \<30) 5. Malabsorption syndrome 6. Abnormal sensitivity to the toxic effects of vitamin D 7. Sarcoidosis 8. Hypervitaminosis D