Methods for targeting the immune checkpoint PD1 pathway for treating pulmonary fibrosis

1. A method for reducing progression of progressive pulmonary fibrosis in a subject, the method comprising:

selecting a subject having idiopathic pulmonary fibrosis (IPF) and a higher level of total protein expression of PD-L1/CD274 in lung tissue or an upregulation of PD-L1/CD274 and PD-L2/CD273 in invasive pulmonary fibroblasts, as compared to a control subject not suffering from pulmonary fibrosis, for treatment for pulmonary fibrosis, wherein the treatment reduces progression of progressive pulmonary fibrosis; and

administering to the subject a pharmaceutical composition comprising a therapeutic amount of a therapeutic agent,

wherein the therapeutic agent comprises an inhibitor of programmed death receptor-ligand 1 (PD-L1) selected from the group consisting of atezolizumab (MPDL3280A, TECENTRIQ), avelumab (BAVENCIO, MSB0010718C), durvalumab (MEDI4736, IMFINZI), MDX-1105, YW243.55.S70, and CA-170.

2. The method of claim 1 , wherein the method improves lung function in the subject.

3. The method of claim 1 , wherein the therapeutic agent is atezolizumab.

4. The method of claim 1 , wherein compared to an untreated control subject having IPF, the therapeutic agent:

(a) decreases the invasiveness of pulmonary fibroblasts in the subject; or

(b) decreases the migration of pulmonary fibroblasts in the subject; or

(c) decreases cell adhesion of pulmonary fibroblasts in the subject; or

(d) decreases pulmonary fibroblast proliferation and differentiation in the subject; or

(e) decreases extracellular matrix production in the subject; or

(f) decreases myofibroblast activation in the subject; or

(g) a combination thereof.

5. The method of claim 1 , wherein compared to an untreated control subject having IPF,

(a) the composition comprises a first therapeutic agent that modulates the programmed cell death pathway in combination with a second therapeutic agent that modulates the programmed cell death pathway in the subject; or

(b) the composition comprises a therapeutic agent that modulates the programmed cell death pathway and a focal adhesion kinase (FAK) inhibitor in the subject.

6. The method of claim 1 , wherein the subject also has upregulation of PD1, PD-L1, PD-L2, or RGMb expression levels in lung tissue of the subject to which the pharmaceutical composition is to be administered, as compared to the control subject not suffering from pulmonary fibrosis.

7. The method of claim 1 , wherein the pharmaceutical composition further comprises a focal adhesion kinase (FAK) inhibitor in addition to the therapeutic agent.

8. A method for reducing progression of progressive pulmonary fibrosis in a subject, the method comprising:

identifying a subject having idiopathic pulmonary fibrosis (IPF) for treatment for pulmonary fibrosis,

wherein upregulation of PD-L1/CD274 and PD-L2/CD273 is detected in invasive fibroblasts from lung tissue of the subject, as compared to a control subject not suffering from pulmonary fibrosis; and

administering to the subject a pharmaceutical composition comprising a therapeutic amount of a therapeutic agent comprising an inhibitor of programmed death receptor-ligand 1 (PD-L1) selected from the group consisting of atezolizumab (MPDL3280A, TECENTRIQ), avelumab (BAVENCIO, MSB0010718C), durvalumab (MEDI4736, IMFINZI), MDX-1105, YW243.55.S70, and CA-170,

wherein the treatment reduces progression of progressive pulmonary fibrosis in the subject.

9. The method of claim 8 , wherein the pharmaceutical composition further comprises a focal adhesion kinase (FAK) inhibitor in addition to the therapeutic agent.

10. The method of claim 8 , wherein elevated expression of RGMb is detected in the lung tissue of the subject, as compared to the control subject not suffering from pulmonary fibrosis.

11. The method of claim 10 , wherein the pharmaceutical composition further comprises a focal adhesion kinase (FAK) inhibitor in addition to the therapeutic agent.

12. The method of claim 8 , wherein compared to an untreated control subject having IPF, the therapeutic amount modulates a programmed cell death pathway, and reduces progression of the progressive pulmonary fibrosis in the subject.

13. The method of claim 8 , wherein compared to an untreated control subject having IPF, the therapeutic agent decreases expression or biological activity of one or more of PD1, PD-L1, PD-L2, or RGMb in the subject.

14. The method of claim 8 , wherein compared to an untreated control subject having IPF, the composition is effective to:

reduce a symptom of pulmonary fibrosis in the subject;

reduce lung hydroxyproline levels in the subject;

reduce lung density of the subject; and/or

reduce total cell count (TCC) in bronchoalveolar lavage fluid (BALF) from the subject.

15. The method of claim 8 , wherein a higher level of total protein expression of PD-L1/CD274 is detected in the lung tissue of the subject, as compared to the control subject not suffering from pulmonary fibrosis.

16. The method of claim 1 , wherein compared to an untreated control subject having IPF, the therapeutic amount modulates a programmed cell death pathway, and reduces progression of the progressive pulmonary fibrosis in the subject.

17. The method of claim 1 , wherein compared to an untreated control subject having IPF, the therapeutic agent decreases the expression or biological activity of one or more of PD1, PD-L1, PD-L2, or RGMb in the subject.

18. The method of claim 1 , wherein compared to an untreated control subject having IPF, the composition is effective to:

reduce a symptom of pulmonary fibrosis in the subject;

reduce lung hydroxyproline levels in the subject;

reduce lung density of the subject; and/or

reduce total cell count (TCC) in bronchoalveolar lavage fluid (BALF) from the subject.