B2C member subscriptions revenue increased by $5.6 million, or 35.8%, to $21.1 million for the
three months ended June 30, 2021 from $15.5 million for the three months ended June 30, 2020. Revenue from our health plan clients increased by $4.9 million, or 432.3%, to $6.1 million for the three months ended
June 30, 2021 from $1.1 million for the three months ended June 30, 2020. Enterprise client contracts increased by 66 clients, or 161.0%, to 107 clients as of June 30, 2021 from 41 clients as of June 30, 2020. This increase
in the number of enterprise clients increased revenue by $2.6 million, or 215.5%, to $3.8 million for the three months ended June 30, 2021 from $1.2 million for the three months ended June 30, 2020.
Revenues increased by $29.1 million, or 100.5%, to $58.1 million for the six months ended June 30, 2021 from $29.0 million for the six
months ended June 30, 2020. The increase was principally driven by increased B2C member subscriptions, an increase in year-over-year revenue from existing health plan clients and the addition of new enterprise clients. B2C member subscriptions
revenue increased by $14.4 million, or 56.8%, to $39.7 million for the six months ended June 30, 2021 from $25.3 million for the six months ended June 30, 2020. Revenue from our health plan clients increased by
$9.7 million, or 580.5%, to $11.4 million for the six months ended June 30, 2021 from $1.7 million for the six months ended June 30, 2020. The increase in the number of enterprise clients increased revenue by
$5.1 million, or 261.3%, to $7.1 million for the six months ended June 30, 2021 from $2.0 million for the six months ended June 30, 2020.
We believe that the appeal of our technology platform, the quality of our providers and the cost of our services will continue to represent the primary
drivers of revenue growth from B2C members and B2B clients.
Costs of revenues. Cost of revenues increased by $6.1 million, or 110.0%, to
$11.7 million for the three months ended June 30, 2021 from $5.6 million for the three months ended June 30, 2020, primarily due to costs associated with an increase of providers on our platform. This increase of providers was
required to service the increased demand for our therapy services in both our B2C and B2B businesses.
Cost of revenues increased by $10.5 million,
or 95.9%, to $21.5 million for the six months ended June 30, 2021 from $11.0 million for the six months ended June 30, 2020, primarily due to costs associated with an increase of providers on our platform. This increase of
providers was required to service the increased demand for our therapy services in both our B2C and B2B businesses.
Total employee provider headcount was
227 as of June 30, 2021.
Gross profit. Gross profit increased by $7.0 million, or 56.7%, to $19.3 million for
the three months ended June 30, 2021 from $12.3 million for the three months ended June 30, 2020. This increase was primarily due to the 73.3% increase in revenues, partially offset by higher cost of revenues due to an increase of
providers on our platform to support our increased demand.
Gross profit increased by $18.6 million, or 103.3%, to $36.6 million for the six
months ended June 30, 2021 from $18.0 million for the six months ended June 30, 2020. This increase was primarily due to the 100.5% increase in revenues.
Research and development expenses. Research and development expenses increased by $2.4 million, or 99.2%, to
$4.8 million for the three months ended June 30, 2021 from $2.4 million for the three months ended June 30, 2020. This was primarily due to an increase of $2.3 million in employee-related costs, inclusive of non-cash stock compensation expense.
Research and development expenses increased by $2.6 million, or 51.0%, to
$7.7 million for the six months ended June 30, 2021 from $5.1 million for the six months ended June 30, 2020. This was primarily due to an increase of $3.0 million in employee-related costs, inclusive of non-cash stock compensation expense, and was partially offset by a decrease of $0.4 million in contractor related costs and $0.3 million in cost savings related to the application of research grant
proceeds.
Total research and development employee headcount increased to 60 employees as of June 30, 2021, as compared to 35 employees as of
June 30, 2020.
Clinical operations expenses. Clinical operations expenses increased by $1.2 million, or 152.0%, to
$1.9 million for the three months ended June 30, 2021 from $0.8 million for the three months ended June 30, 2020. This was primarily due to an increase of $0.6 million in employee-related costs, inclusive of non-cash stock compensation expense, and $0.5 million in provider recruiting costs.
Clinical operations expenses
increased by $2.4 million, or 143.9%, to $4.0 million for the six months ended June 30, 2021 from $1.6 million for the six months ended June 30, 2020. This was primarily due to an increase of $1.1 million in
employee-related costs, inclusive of non-cash stock compensation expense and $1.1 million in provider recruiting costs.
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