A Phase 2, Open-Label Study Evaluating the Efficacy, Safety, Tolerability, and Pharmacodynamics of GS-9973 in Combination With Idelalisib in Subjects With Relapsed or Refractory Hematologic Malignancies

Inclusion Criteria:

- Diagnosis of B-cell iNHL, DLBCL, MCL, or CLL as documented by medical records and
with histology based on criteria established by the World Health Organization

- For institutions that have Phase 3 protocols studying idelalisib (GS-1101); subjects
with malignancies being studied in these protocols must have failed screening and be
registered as a screen failure in the respective idelalisib protocol

- Prior treatment for lymphoid malignancy

- Presence of radiographically measurable lymphadenopathy or extranodal lymphoid
malignancy

- Discontinuation of all therapy for the treatment of cancer ≥ 3 weeks before the start
of study drug

- All acute toxic effects of any prior antitumor therapy resolved to Grade ≤ 1 before
the start of study drug

- Karnofsky performance status of ≥ 60

- Life expectancy of at least 3 months

Exclusion Criteria:

- Known histological transformation from iNHL or CLL to an aggressive form of NHL (ie,
Richter transformation)

- Known active central nervous system or leptomeningeal lymphoma

- Presence of known intermediate- or high-grade myelodysplastic syndrome

- Current therapy with agents that reduce gastric acidity, including but not limited to
antacids, H2 inhibitors, and proton pump inhibitors

- Evidence of ongoing systemic bacterial, fungal, or viral infection at the time of
start of study drug

- Ongoing liver injury

- Ongoing or recent hepatic encephalopathy

- Ongoing drug-induced pneumonitis

- Ongoing inflammatory bowel disease

- Ongoing alcohol or drug addiction

- Pregnancy or breastfeeding

- History of prior allogeneic bone marrow progenitor cell or solid organ
transplantation

- Ongoing immunosuppressive therapy

- Concurrent participation in an investigational drug trial with therapeutic intent