TG Therapeutics, Inc. Announces Presentations of its Proprietary Combination of TG-1101 plus TGR-1202 as well as TGR-1202 as a Single Agent in Ongoing Phase I/Ib Dose Escalation Clinical Studies Triple therapy cohort of

TG Therapeutics, Inc. Announces Presentations

of its Proprietary Combination of

TG-1101 plus TGR-1202 as well as TGR-1202 as a Single Agent in Ongoing Phase

I/Ib Dose Escalation

Triple therapy cohort of the combination study to be

presented separately as an oral presentation tomorrow morning, Monday, June 1st, 2015, at 51st American Society of Clinical

Oncology (ASCO) Annual Meeting

Data from both studies (over 135 patients combined between

single agent and combination studies) continues to demonstrate a favorable safety profile with a high level of activity and a significant

dose-response relationship observed

85% (11 of 13) CLL/SLL patients treated at the higher

doses of 1202 as a single agent and in combination with TG-1101 achieved a nodal response, with most CLL patients achieving a Partial

Response per iwCLL (Hallek 2008) criteria with patients on study pending further assessment

50% (3 of 6) Overall Response Rate (ORR) in Follicular

Lymphoma (FL) patients treated with the higher doses of single agent TGR-1202

41% (3 of 7) ORR in patients with Diffuse Large B-Cell

Lymphoma (DLBCL) treated at the higher doses of the combination of TG-1101 and TGR-1202, and a clinical benefit rate (patients

achieving stable disease or better) of 86% (6 of 7)

TGR-1202 alone and in combination with TG-1101 continues

to be well-tolerated with limited Grade 3/4 events and 5% of the patients across both studies discontinuing for adverse events,

none of which were hepatic toxicity or colitis, with over 50 patients between both studies on therapy 6+ months

NEW YORK, May 31, 2015-- TG Therapeutics,

Inc. (Nasdaq:TGTX), today announced clinical results from two ongoing studies of its oral, once-daily, PI3K delta inhibitor,

TGR-1202, as a single agent and in combination with TG-1101 (ublituximab), the Company's novel glycoengineered anti-CD20

monoclonal antibody. Data from these two Phase I dose escalation studies are being presented today at the morning poster sessions

(8-11:30am CT) during the 51st American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, IL.

Michael S. Weiss, the Company's Executive Chairman

and Interim CEO commented on the data, "We continue to be impressed with the safety and efficacy profile of TGR-1202, as a

single agent, and in combination with TG-1101, and we believe the high level of activity and our differentiated safety profile

seen to date, where elevations of ALT/AST are rarely seen and colitis has yet to be observed will position our proprietary combination

to play an important role in the management of patients with B-cell malignancies. Unfortunately, in the United States

alone, approximately 100,000 individuals will be diagnosed with NHL and CLL per year and a similar amount will relapse from their

disease annually. Even with the best new treatments options, few of these patients will actually be cured. We believe the

safety, and activity profile seen to date with TG-1101 plus TGR-1202 will compare quite favorably to alternative doublet treatment

options and provides us a strong base regimen to build upon as we push further into novel triple and quad therapies."

Mr. Weiss, continued, "As we are nearing completion of our dosing work, we are excited to turn our attention to the next

phase of development for our proprietary 1303' combination in CLL and NHL, with the goal of launching at least two

Phase 3 studies before the end of this year. These new Phase 3 studies will complement our on-going GENUINE Phase 3 trial

exploring the combination of TG-1101 plus ibrutunib in previously treated patients with high-risk CLL, which is now aggressively

recruiting patients."

The following summarizes the posters presented

Abstract Number 8548: Ublituximab plus

TGR-1202 activity and safety profile in relapsed/refractory B-cell NHL and high-risk CLL

Today's poster presentation includes data from

55 patients with advanced relapsed and refractory high-risk CLL and NHL patients treated with the combination of TG-1101 and TGR-1202

at doses through 1200 mg micronized QD.

Highlights from this poster include:

Overview of the data presented on TGR-1202

in combination with TG-1101 (ublituximab):

Safety and Tolerability

TG-1101 in combination with TGR-1202 (referred

to as "TG-1303") has been well tolerated in the 55 patients evaluable for safety, at all dose levels up through 1200

mg micronized, the highest dose level tested to date. Day 1 infusion related reactions (IRR) have been the most frequently reported

adverse event in 29% of patients, with all but 1 event being Grade 1 or 2 in severity and occurring more frequently in patients

with CLL. Neutropenia was the only Grade 3/4 event reported in > 5% of patients (24%), however, the inclusion criteria in this

study allowed enrollment of patients with existing baseline Grade 3 neutropenia. Of the 55 patients to date, only 3 (5%) have discontinued

due to an adverse event. Notably, with respect to preliminary long-term tolerability, 18 patients (33%) have now been on TG-1101

plus TGR-1202 for 6+ months, with no reported events of colitis.

The study design evaluated sequential dosing

cohorts with fixed doses of TG-1101 and escalating doses of TGR-1202 with both the original formulation and the micronized formulation,

which have been classified based on exposure into "lower dose" and "higher dose" cohorts (higher dose classified

as 1200 mg of the original formulation or 600 mg of the micronized formulation). A significant dose-response relationship was

observed between the high and low doses in all 39 patients evaluable for efficacy at the time of the study cut-off, particularly

in the NHL patients (FL, DLBCL), where a significant increase in complete response rates was observed in the higher dose group.

A breakdown of responses by high and low dose is illustrated in the table below:

Of the 15 patients evaluable for efficacy with

FL and Marginal Zone lymphoma (MZL), the dose-response relationship observed was significant, with the higher dose cohorts demonstrating

a 64% ORR, with 2 Complete Responses compared to a 25% ORR in the lower dose cohort. The same trend has been observed in the more

aggressive lymphomas (DLBCL and Richter's) where 50% (4 of 8) achieved an objective response (2 CR and 2 PR) compared to

no responses seen in the lower dose cohorts. Of note, 86% (6 of 7) of the DLBCL patients in the higher dose cohorts who had at

least one efficacy assessment (week 8) remain on study progression free, with 71% (5 of 7) having GCB subtype, which has historically

been less responsive to BCR targeted therapy.

As seen with TGR-1202 as a single agent, responses

have been shown to improve over time, with 3 of the 5 CR's achieved at subsequent efficacy assessments.

Commenting on the combination data, Dr. Matthew

Lunning, Division of Hematology/Oncology, University of Nebraska Medical Center and lead author of the presentation stated, "We

continue to remain impressed not only by the safety profile of the combination, but especially by the efficacy demonstrated in

this very advanced CLL and NHL patient population. We look forward to continuing enrolling in the CLL and NHL expansion cohorts,

with a focus on refractory DLBCL patients who have very limited options, to further evaluate this novel and exciting combination."

Dr. Lunning continued, "The safety and efficacy profile of the combination of TG-1101 and TGR-1202 is well suited as a platform

regimen for further combination studies and I look forward to the presentation of the first ever triple combination of TG-1101

plus TGR-1202 plus ibrutinib in an oral presentation tomorrow to be given by Dr. Nathan Fowler of MD Anderson."

Abstract Number 7069: "Clinical activity

and safety profile of TGR-1202, a novel once daily PI3K delta inhibitor, in patients with CLL and B-cell lymphoma"

Today's poster presentation includes data from

66 patients with relapsed and refractory hematologic malignancies treated with single agent TGR-1202 at escalating doses up through

1200 mg micronized QD. Highlights from this poster include:

Overview of the data presented on single

Safety and Tolerability

In the 66 patients evaluable for safety, TGR-1202

has been well-tolerated with no dose-related trends in adverse events observed and patients on study for upwards of 2+ years. Grade

3 events continue to be limited with only 3 patients (< 5%) having discontinued study due to an adverse event, none of which

were for hepatic toxicity or colitis which have been common and potentially serious and life threatening with other PI3K-delta

inhibitors. Neutropenia was the only Grade 3/4 event reported in >10% of patients (11%). Notably, with respect to preliminary

long-term tolerability, 29 patients (44%) have now been on TGR-1202 for 6+ months, with some patients on TGR-1202 for 2+ years,

with no reported events of colitis.

Significant clinical activity was observed in

patients with CLL treated at doses 800 mg with 88% of CLL patients (14 of 16) achieving a nodal PR, and 10 of 16 (63%) of patients

achieving a response per iwCLL (Hallek 2008) criteria. The remaining two patients exhibited nodal reductions and remain on study