On this page of StockholderLetter.com we present the latest annual shareholder letter from Phio Pharmaceuticals Corp. — ticker symbol PHIO. Reading current and past PHIO letters to shareholders can bring important insights into the investment thesis.

 •  5/8/2024 Letter Continued (Full PDF)
 •  6/9/2023 PHIO Stockholder Letter
 •  More "Drugs & Pharmaceuticals" Category Stockholder Letters
 •  PHIO Benford's Law Stock Score = 31

PHIO Shareholder/Stockholder Letter Transcript:

2023
Phio Pharmaceuticals Corp.
Annual Report


Dear Shareholder:
On behalf of the Phio Board of Directors and management team, I want to thank you for your
investment in our Company. Our objective is to drive shareholder value for you as we continue
on our mission to eliminate cancer in ways that others cannot. We strive to execute our strategy
effectively and efficiently, leveraging our patented INTASYL   technology platform which is
designed to make immune cells more effective at killing cancer cells.
Last year I described our plan to transition our primary business model from discovery research
to human drug development. Our goal at that time was to deploy our INTASYL technology in a
human clinical trial. Having established preclinical safety and proof of concept in various types
of solid tumor models, we elected to target skin cancer, and in particular cutaneous squamous
cell carcinoma (cSCC). We successfully demonstrated that in preclinical studies our lead
compound PH-762 silences the production of the PD-1 protein, which disguises tumor cells from
our body  s innate T-cell tumor killing action. The role of PD-1 in disguising solid tumors was
initially substantiated by a few large pharma companies with their monoclonal antibody (mAB)
biologics. The systemic infusion of mAB  s could attack PD-1 already present on the surface of
the cell. In contrast, we established that Phio  s PH-762 compound could shut down or silence
the production of PD-1 at its source within the T-cell before it could migrate to the cell surface.
Moreover, PH-762 could be administered by intralesional injection direct to the tumor site
instead of through systemic infusion. Phio  s form of administration essentially reduces the risk of
off target side effects, in particular, auto immune reactions common with mAB systemic infusion.
Phio  s administration by injection would also provide convenience to physician and patient,
allowing for treatment in the physician  s office.
In April of 2023 we submitted an IND (Investigational New Drug Application) to the FDA with a
goal to receive approval to commence the first in human Phase 1b dose escalation study to
treat late stages of melanoma, Merkel cell and cutaneous squamous cell carcinoma with PH762. Approximately one month later we received clearance to commence a study in the late
stages of these diseases, but were also granted clearance to treat early stages I&II of cSCC for
which there is no drug currently approved in the U.S. The current standard of care is surgical
intervention. This approval to study early stages of cSCC opened a significant market
opportunity. Cutaneous squamous cell carcinoma represents the 2nd largest incidence of solid
tumors in the U.S. in the human body, only exceeded by basal cell carcinoma. Cutaneous
squamous cell carcinoma represents approximately 1.8 million incidences of which Stages I&II
comprise over 75% of these tumors. The capture of just a modest single digit market share in
this segment aligned with a per treatment regimen price point acceptable to drug reimbursement
plans could reasonably yield revenue dollars in excess of $1 billion annually.
With FDA approval to proceed with our study, we sought out and successfully concluded
agreements with 4 clinical investigation sites, geographically dispersed, representing a
combination of prestigious universities, medical centers and private clinics. Today I am happy to
report we are treating the last patient in the first dosing cohort of 5 increasing-dose cohorts of
patients. It is our goal to advance through the 4 additional cohorts over the next 12 months to
complete the enrollment of the clinical trial sometime in 2nd quarter 2025.
In parallel with conducting the clinical trial, we initiated cost improvement and operational
efficiency programs. On March 31st of this year, we terminated our lease on a 7,600 square foot
facility in Marlborough MA., serving both research and administration needs. With a reduction of

6 discovery scientists, we transferred a more focused activity to a smaller footprint consisting of
2 scientists in a 321 square foot incubator space in the city of Worcester. Our administrative
staff of 2 individuals now conduct their activities virtually. Development personnel also work
virtually. Clinical trial activity is supported by 2 senior in-house experts with combined
experience exceeding 50 years. They, along with a lean but experienced network of specifically
skilled individual consultants drive the development program. We have the added benefit of
these individuals having worked together cross functionally in a prior pharma company. In this
manner we deploy personnel as needed to maximize cost efficiencies.
We are also rationalizing our intellectual property portfolio, broadening protections on our
primary and backup compounds, and strengthening claims on compounds which we have
targeted for out-license to 3rd parties. Currently, the proprietary protections on our lead and
backup compounds extend beyond the year 2040 with the inclusion of patent term restoration.
Our out-license efforts target companies in the biotech and dermatology space to offer license
opportunities for INTASYL compounds that are not of our primary focus, but which may be
complimentary to their technologies and not directly competitive to our core business targets.
As we progress through this fiscal year we will continue to enhance our visibility to
shareholders, industry and medical societies. We recently initiated a one-minute Phio
infomercial campaign across a number of cable and streaming services which portrays our
medical/research focus in the field of solid tumors. We are also presenting various medical
abstracts and study posters at many of the prestigious medical society meetings which address
cancer and dermatology. We believe these actions will expand our reach to a broader base of
investors and potential corporate business development partners.
In summary, I wish to thank you for your interest and continued support as we strive to realize
our vision:   discovering new pathways toward a cancer free future  . I hope this short update has
been helpful to you in understanding our strategy and progress. We look forward to exceeding
your expectations.
Sincerely,
Robert Bitterman
Chairman, President and CEO



 5/8/2024 Letter Continued (Full PDF)