Assess the Safety, Pharmacokinetics, Pharmacodynamics and Clinical Activity of RXC007 in Idiopathic Pulmonary Fibrosis

The purpose of the study is to assess the safety and tolerability of RXC007 when given for 12 weeks (84 days), alone and in combination with nintedanib or pirfenidone.

The purpose of this study is to investigate the study drug RXC007.

The main objectives of this study are as follows:

* To determine the safety and tolerability (degree to which side effects of a drug can be tolerated) of RXC007 when it is administered as twice daily doses over a period of up to 12 weeks (84 days).
* To investigate the concentration of RXC007 (how much drug is in your blood), how this changes over a period of time and to evaluate whether there are differences in the concentration between different dose strengths of RXC007.
* To investigate the effect of RXC007 on the body (known as pharmacodynamics) by analysing the levels of certain biomarkers in the body and to assess the effect of RXC007 on markers associated with Idiopathic Pulmonary Fibrosis (IPF). Biomarkers are markers within the body such as a molecule or compound made by cells in the body, which can be measured and used to identify a particular disease.

Eligibility Criteria:
Inclusion Criteria:

* Aged ≥40 to 80 years at the time of signing the informed consent.
* Diagnosis of IPF within 5 years of Screening based on the modified ATS/ERS/JRS/ALAT IPF guidelines for diagnosis and management of IPF (Raghu et al, 2018) and confirmed on independent central imaging review.
* Combination of HRCT pattern, as assessed by central reviewers, consistent with diagnosis of IPF (see the modified ATS/ERS/JRS/ALAT IPF guidelines \[Raghu et al, 2018\]).
* FVC % predicted ≥50% predicted of normal at Screening, with no clinically significant deterioration between the Screening Visit and randomisation, as determined by the Investigator.
* DLco (Hb-adjusted) at screening ≥30%.
* In the main study, participants receiving treatment for IPF with nintedanib or pirfenidone are allowed if on treatment for at least 3 months and on a stable dose for at least 4 weeks prior to Screening and during Screening.
* In patients who are not on any treatment for IPF but have previously received nintedanib or pirfenidone, there needs to be a washout period ≥4 weeks prior to Screening.
* No clinically significant abnormalities, in the opinion of the investigator, in vital signs (e.g., blood pressure, pulse rate, respiration rate, oral temperature) within 28 days before first dose of IMP.

Exclusion Criteria:

* Currently receiving or planning to initiate treatment for IPF with agents not approved for that indication.
* FEV1/FVC ratio \<0.7 at Screening, pre-bronchodilator use.
* Lower respiratory tract infection requiring antibiotics within 4 weeks of Screening or during Screening.

  4. The extent of emphysema in the lungs exceeds fibrosis, based on central review of HRCT scans.
* Need for continuous oxygen supplementation, defined as \>15 hours/day.
* Acute IPF exacerbation within 6 months of Screening or during Screening.
* Clinical diagnosis of any connective-tissue disease (including, but not limited to, scleroderma, polymyositis/dermatomyositis, systemic lupus erythematosus, and rheumatoid arthritis) or a diagnosis of interstitial pneumonia with autoimmune features as determined by the Investigator applying the recent ERS/ATS research statement \[Fischer et al 2015\]. Note: Serological testing is not needed if not clinically indicated.
* Disease other than IPF with a life expectancy of less than 12 weeks.

Additional exclusion criteria for the Translational Science Sub Study

* Participants with any contra-indication to bronchoscopy and alveolar lavage including tracheal stenosis, pulmonary hypertension, severe hypoxia, or hypercapnia.
* Patients in the sub study are not permitted to receive nintedanib or pirfenidone within 3 weeks of randomisation and throughout the Treatment period. (Note: background IPF treatment should not be stopped for the purpose of eligibility)