Inclusion Criteria:

          -  Histologically confirmed metastatic non-small cell lung cancer with TKI-sensitive EGFR
             mutation through CLIA certified lab.

          -  Measurable disease by RECIST 1.1 with at least one lesion accessible for core biopsy.

          -  Planning to initiate treatment with standard of care osimertinib 80 mg QD. In order to
             continue treatment with osimertinib + APL-101, patients must have received at least 8
             and no more than 12 weeks of SOC osimertinib without disease progression.

          -  At least 18 years of age.

          -  ECOG performance status ≤ 1

          -  Normal bone marrow and organ function as defined below:

               -  Absolute neutrophil count ≥ 1,500/mcL

               -  Platelets ≥ 100,000/mcL

               -  Hemoglobin ≥ 9 g/dL (transfused Hgb allowed)

               -  Total bilirubin ≤ 1.5 mg/dL or ≤ 26 µmol/L

               -  AST(SGOT)/ALT(SGPT) ≤ 2.5 x institutional upper limit of normal (IULN) (≤ 5.0 x
                  IULN if liver metastases)

               -  Creatinine ≤2 x IULN or Creatinine clearance calculated by Cockcroft-Gault
                  formula ≥60 ml/min

               -  Serum calcium (after correcting for albumin level) ≤ IULN

               -  Serum phosphorus ≤ IULN

          -  The effects of APL-101 on the developing human fetus are unknown. For this reason,
             women of childbearing potential and men must agree to use adequate contraception
             (hormonal or barrier method of birth control, abstinence) prior to study entry and for
             the duration of study participation. Should a woman become pregnant or suspect she is
             pregnant while participating in this study, she must inform her treating physician
             immediately. Men treated or enrolled on this protocol must also agree to use adequate
             contraception prior to the study and for the duration of the study.

          -  Ability to understand and willingness to sign an IRB approved written informed consent
             document (or that of legally authorized representative, if applicable).

        Exclusion Criteria:

          -  Prior treatment with osimertinib in the metastatic setting (outside of osimertinib
             given immediately prior to and during the enrollment period). Prior treatment with
             chemotherapy in the neoadjuvant, adjuvant, or first-line metastatic setting is however
             allowed.

          -  Prior immunotherapy and/or frontline EGFR-directed treatment in the metastatic
             setting. EGFR directed therapy in the adjuvant setting is permitted, as long as the
             disease-free interval between completion of adjuvant therapy with EGFR directed
             therapy and initiation of osimertinib is more than or equal to 1 year.

          -  Disease refractory to osimertinib, given immediately prior to and during enrollment
             period.

          -  A history of other malignancy with the exception of:

               -  malignancies for which all treatment was completed at least 1 year before
                  registration and the patient has no evidence of disease; or

               -  known indolent malignancies, or malignancies that do not require active treatment
                  and are unlikely not alter the course of treatment of metastatic NSCLC per
                  treating physician.

          -  Currently receiving any other investigational agents or herbal medications

          -  Presence of symptomatic central nervous system metastases or neurologically unstable
             CNS symptoms (unable to taper steroids). Patients with treated brain metastases are
             eligible. Patients with asymptomatic brain metastases prior to initiation of
             osimertinib will be eligible to receive combination therapy as long as their disease
             is shown to be responsive to osimertinib.

          -  A history of allergic reactions attributed to compounds of similar chemical or
             biologic composition to APL-101, osimertinib, or other agents used in the study.

          -  Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection, immune deficiencies, hepatitis B, untreated hepatitis C, uncontrolled
             diabetes, uncontrolled hypertension, symptomatic congestive heart failure, unstable
             angina pectoris, myocardial infraction within the past 6 months, uncontrolled cardiac
             arrhythmia, or prolonged QTc interval > 450 ms.

          -  Uncontrolled or symptomatic pleural or pericardial effusion.

          -  Decompensated heart failure or heart failure with reduced ejection fraction (<50%)

          -  Major surgery within 30 days prior to first day of study treatment.

          -  Poorly controlled diarrheal or gastrointestinal disorders (grade 2 or higher diarrhea,
             nausea, or vomiting at baseline).

          -  Pregnant and/or breastfeeding. Women of childbearing potential must have a negative
             pregnancy test within 14 days of study entry.

          -  Unresolved grade 2 or higher treatment-related toxicities (with the exception of
             endocrine abnormalities as a result of immunotherapies that are being managed with
             hormonal supplementation). However, if the treating physician is under the impression
             that the toxicity under question is unlikely to affect study participation, patient
             eligibility can be discussed with the PI on a subject by subject basis. After
             enrollment to this study, osimertinib-related toxicities must resolve to ≤ grade 1
             before patient may begin combination therapy.

          -  Presence of interstitial lung disease